1974-77 Kawasaki KZ400 Shop Manual

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SHOP MANUAL

SHOP MANUA

KZ400D(1974~— 1977)
K24005(1975~ 1977)

Kawasaki

KZ400

© Kawasaki Heavy Industrie, Ltd. 1974, 1975, 1976, 1978 5th Revision: Aug 25, 1978 M

Foreword

This manual is designed primaniy tor use by motorcycle mechanics in a properly equipped shop
although it contains enough detail and basic information to make it useful to the motorcycle user
who desires to carry out his own basic maintenance and repair work, Since a certain basic knowledge
of mechanics, the proper use of tools, and workshop procedures must be understood in order to carry
out maintenance and repair satisfactorily, the adjustments, maintenance, and repair should be carried
out only by qualified mechanics whenever the owner has insufficient experience or has doubts as to
his ability te do the work so that the motorcycle can be operated safely.

In order to perform the work efficiently and to avoid costly mistakes, the mechanic should read
the text, thoroughly familiarizing himself with the procedures before starting work, and then do
the work carefully in a clean area. Whenever special tools or equipment is specified, makeshift tools or
equipment should not be used. Precision measurements can only be made if the proper instruments
are used, and the use of substitute tools may adversely affect safe operation of the motorcycle.

This manual is divided into the following four sections:

(1) Adjustment
The adjustment section gives the procedure for all adjustments which may become necessary
periodically and which do not involve major disassembly,
(2) Disassernbly
This section shows the best method for the removal, disassembly, assembly, and installation which
are necessary for maintenance and repair. Since assembly and installation are usually the reverse
of disassembly and removal, assembly and installation are not explained in detail in some cases.
Instead, assembly notes and installation notes are provided to explain special points.
(3) Maintenance and Theory of Operation
The procedures for inspection and repair are described in detail in this section, An explanation
of the structure and functioning of each of the major parts and assemblies is given to enable the
mechanic to understand better what he is doing.
(4) Appendix
The appendix in the back of this manual contains miscellaneous information, including a special
tool list, a torque table, a table for periodic maintenance, and a troubleshooting quide.

Since this Shop Manual is based on units of the K2400 presently on the market, there may be minor
discrepancies between some vehicles and the illustrations and text in this manual. Major changes
and additions pertaining to later year units will be explained in a supplement following the appendix
or by a new edition. |

Places marked with an asterisk (*) indicate where the latest revisions or additions have been made
in the text,

7

2 TABLE OF CONTENTS

Table of Contents

FOREWORD .............. he Rtas Be 1 CLUTCH, PRIMARY CHAIN ...... ace 49
SPECIFICATIONS. .......... Ja aL le oe CLUTCH RELEASE. ............ eae. Ge
ENGINE PERFORMANCE CURVES... 7 ENGINE SPROCKET........... eee
RUNNING PERFORMANCE CURVES,. 8 NEUTRAL INDICATOR SWITCH......, 53
ADJUSTMENT ENGINE OIL PUMP ........... ofarallets,. SH
THROTTLE CABLES ........ ne 9 EXTERNAL SHIFT MECHANISM....... 54
CARBURETORS ('74~'76 Model)... ... . 9 TRANSMISSION... 00002 cea nnes 56
AG sh ose age ee eoceraere ayevp tase a Waele 11 KICKSTARTER..... 2-2 eee aa ewe ease 63
SPARK PLUGS... ......0c00000ceans 12 OIL PRESSURE RELIEF VALVE....... 64
IGNITION TIMING..........00000055 12 BALANCER MECHANISM............ 65
VALVE CLEARANCE... .. Sis twos ees 14 CRANKSHAFT, CAMSHAFT CHAIN..... 67
CAMSHAFT CHAIN... .......0000005 15 CAMSHAFT CHAIN GUIDE (FRONT).... 71
STEERING...... SC Th ey ee wa [| CAMSHAFT CHAIN GUIDE (REAR},.... 72
WHEEL BALANCE... 0... ...4 006s cere ts - = —
FRONT BRAKE LEVER FRONT WHEEL (Only on KZ400D),..... 72
{Only on KZ400D) ............... 17 FRONT WHEEL (Only on KZ4005)...... 74
FRONT BRAKE (Only on K24005),...... 17 REAR WHEEL... 2... ee eee eee, FF
REAR BAAKE......... eae sae wane 19 Li. Se os eer eres 80
BRAKE LIGHT SWITCH ............. 20 PRS is 5 whiacges wecian tp evel ere pote ee tel ate eral 80
DRIVE: CHAIN ieee cA ee 20 SON Bob a ovate ld cortareio Gata nin ord lafaln'ers 81
REAR SHOCK ABSORBERS ...... eee a DISC BRAKE (Only on KZ400D) ....... 81
HEADLIGHT ace :ccccccesete te cieresncee se Say DRIVE. CHAIN «onc iaccie eo eececane eres cece 85
BORN istccerescaurtieietaica cea caintswsatetereie, oat REAR SPROCKET, WHEEL COUPLING .. 86
DISASSEMBLY HANDLEBAR,..........6.- autetal wiles Bs
INTRODUCTION TO DISASSEMBLY..... 23 BRAKE CABLE (Only on KZ4005),..... 88
ENGINE esos ecaeiee's oan SreteWlarethew Near CLUTCH CABLE oso iccc esse. cence oe ota 89
AIR CLEANER ELEMENT............ 27 THROTTLE CABLES. ....... ain fas adc be 90
OWL FILTER. ....-.cccceces Fein fo 27 SPEEDOMETER CABLE ............. 91
WOLF PE ES ioc cnse ase ntecatieeie lees © wretata 28 TACHOMETER CABLE.........+.. -» OF
FUEL SUANKG. 6 casio wenleds vain o/s 28 SPEEDOMETER ....-.- eee eee euee 81
CARBURETORS)... ci cceeresceeees 28 TACHOMETER. .... cite wae eees teee 8
ROCKER ARMS................... 30 HEADLIGHT UNIT............. Wiitle: Ba
fn fc FP oly Goer oe ene oe 33 INDICATOR LIGHTS ......... Mirae Pee 92
CYLINDER HEAD..... Rn er | 3 IGNITION SWITCH... ........: eirpal a 92
VALVES, VALVE GUIDES ........... 38 FRONT FORK o.oo ee ccciieiete eee wee 93
CYLINDER BLOCK. 2... ace eee eee 40 STEERING STEM... cece ees 8S
PISTON, PISTON RINGS... 0... 0.00005 41 STEERING STEM BEARING .......... 97
DYNAMO FIELD COIL........., Sayan ae SWING ARM ......---.-- wo i ece spin ins 98
DYNAMO ARMATURE.............. 44 REAR SHOCK ABSORBERS .......... 100
STARTER MOTOR CLUTCH (Only on MAINTENANCE AND THEORY OF
(KZ24000), DYNAMO ROTOR....... 45 OPERATION
STARTER MOTOR CHAIN (Only on Al PGE EANGR§ v-siicsreiecseecee navece aie) WOT
{KZ400D), SPROCKETS ........... 46 CARBURETORS: (icc. c. 008 sinew 102
STARTER MOTOR (Only on KZ400D) ,.. 46 GARISH ABT ies 4vacecccatiecsccewitia le seats 107
IGNITION COIL........ ite ee CAMSHAFT CHAIN, CHIAN GUIDES.... 108
CONTACT BREAKER.......... Seay, | ROCKER ARMS, SHAFTS............ 109
CONDENSER |. oss cet cyan eae se 4g CYLINDER HEAD, VALVES.......... . 109

TIMING ADVANCER .. 2... 2c enna 43 CYLINDER BLOCK, PISTONS......... 113

CRANKSHAFT, CONNECTING RODS.... 116

BALANCER MECHANISM........ eee ES
O07 ho: Deere rrer ery rarer arene rarer 121
PRIMARY CHAIN «0 ac0ce:acecarerncececeecececee Lee
TRANSMISSION . oc eee ee eee es 124
KIGKSTARTER: ocietccelccareletece eietw eis ees 127
ENGINE LUBRICATION............. 128
PUELSTIAN Recterctcttietetstscetatesnteis ise veteta (Natu
WHEELS oirartctetocteltetets a tabata aia Tela iiaita 133
TIRES... 65 5s Seer seta th arr ee cer URE:
alo Po = PeeteciPirerechch mciCmcicEc in CR IRCICEE 137
PURE sotet riick te tatetatertetr ter: wiv iete sre esreracy Lets
GREASE SEALS, WHEEL BEARINGS. ... 138
REAR WHEEL COUPLING............ 138
DRIVE CHAIN....... eoueieiehebcieteteietaks ULL aee
SP ROCK ETS Sirecicecnmininicsssscivieletitiets orcs 140
DISC BRAKE (Only on KZ400D)..... 140
BRAN Borein ererdicecarataisentshaieter seis ie iaieanee 145
STEERING STEM. cic ee ee 148
FRPCHNT, FOR cece were ee face a fate a es 148
REAR SHOCK ABSORBERS .......... 151
SWING ARM ......... oleate cela tavevare late st Oe
MUFFLERS...... seeierete eaetdie} sielesereecm tn
EMD! Sivelecstes stevee es SOOO OIC 154
FREER so ece ote. cece centctt erase sie fekrvere 157
REGULATOR ivccrre rece ere netete-ayavavetataratays}o (Oo
BATTERY vaccsve eee es coerce ees ee IGT
IGNITION SYSTEM 2 ees 164
TIMING ADVANCER ....000000. see» 166

SPARK PLUGS. ..3. ca ee ee ble eee ee 1G
STARTER MOTOR CIRCUIT

(Only:on KZ400B) . 0... ee es 167
STARTER MOTOR CLUTCH, CHAIN

(Only on K2Z400D) ....... ain ievat atk 170
IGNITION SWITCH ..........25 Aa A
HEADLIGHT CIRCUIT .............. 1a |
BRAKE LIGHT CIRCUIT......... aoe) I |
TURN: SIGNALS ......0 6 scree toe 175
HORW scoters wcareteceteceret ene Bee koe hele cee

SPEEDOMETER, TACHOMETER ....... 176
APPENDIX

SPECIAL TOOLS 0.00 cece ene : VW?
PERIODIC MAINTENANCE,..... Streattoel a!
TORQUE TABLE vices ie eee ees 183

POINTS REQUIRING USE OF A NON-
PERMANENT LOCKING AGENT..... 185

TABLE OF CONTENTS 3

TROUBLESHOOTING GUIDE ......... 186
WIRING DIAGRAM .........2 08000. 189
SUPPLEMENT
ADJUSTMENT
CARBURETORS 3... 200s ee ee ee ees 193

MAINTENANCE AND THEORY OF
OPERATION

CARBURETORS (‘77 Model™) ......... 195
APPENDIX

WIRING DIAGRAMS. ........0006 00 201
TIN DPIS oo aca ce 5 oie n seine = Weta rerets ceretatei ans 205

Dimension
Overall length

Overall width
Overall height
Wheelbase

Road clearance

Dry weight

Fuel tank capacity
Performance

SS % mile (O~ 400 m)

Climbing ability

Braking distance

Minimum turning radius
Engine

Type

Bore and stroke

Displacement

Compression ratio

Maximum horsepower

Maximum torque

Valve timing
Inlet

Exhaust

Carburetors
Lubrication system
Engine oil

Engine oil capacity

Starting system
Ignition system
Ignition timing

Spark plugs
Transmission

Type

Clutch

Gear ratio: Ist
end
3rd
4th
Sth

SPECIFICATIONS

# * , =
Specifications
K2400D
US 2,080 mm
Us 810 mm
European 775mm
US. 1,120 mm
European 1,050 mm
US 1,360 mm
European 1,370 mm
125 mm
170 kg
1428
us 14.4 sec
European 14.6 sec
24°
13.5 m @50 kph
2.am
SOHC 2 cylinder, 4 stroke, air-cooled
64 x 62 mm
398 cc
9.4:1
US 36 HP @8,500 rpm
US 3.3 kg-m @7,500 rpm
Open 26° BTDC
Close 74° ABDC
Duration 280° Total
Open 68.5° BBDC
Close 31.5° ATDC
Duration 280° Total
Keihin VB32 x 2
Forced lubrication (wet sump)
SE class SAE 10W40, 10W50, 20W40, or
Less filter 2.6 2
Total incl. filter 3.0 &
Electric and kick
Battery and coil

From 10° BTDOC @1,100 rpm
to 40° BTDC @2,800 rpm
ND W24ES or NGK B8SES

5-speed, contant mesh, return shift
Wet, multi disc

2.571 (36/14)

1.684 (32/19)

1.273 (28/22)

1.040 (26/25)

0.889 (24/27)

KZ4008

790 mm

1,100 mm

= = = Lt = - = =

20W50

Kick

6 SPECIFICATIONS

Primary reduction ratio
Final reduction ratio US @®

European

Overall drive ratio US @
European

Electrical Equipment

Generator (Dynamo)

Regulator

Ignition coil

Battery

Starter

Headlight type US
European

Headlight US
European

Tail/Brake light US
European

Speedometer light

Tachometer light

Neutral indicator light

High beam indicator light

Turn signal lights US
European

Turn signal indicator light

Oil pressure indicator light

Brake light failure indicator light

Horn

City light European
Frame

Type

Steering angle

Castor

Trail

Tire size Front
Rear

Suspension Front
Rear

Suspension stroke Front
Rear

Front fork oil capacity (each fork)

Front fork oil type
Brakes
Type Front
Rear
Brake drum inside dia. Front
and width Rear
Disc diameter

KZ400D

2,435 (56/23)
3.000 (45/15)
2.933 (44/15)
6.493 (5th)
6.348 (5th)

Nippon Denso 021000-3560
Nippon Denso 026000-2490
Nippon Denso 029700-3430
Yuasa 12N 12A-4A-1
{12V 12AH)
Mitsuba SM242
Seald beam
Semi-sealed
12V 50/35W
12V 35/35W ©12V 36/36W
12V 8/27W
12V 5/21W
12V 3.4W x 2
12V 3.4W x 2
12V 3.4W
12V 1.7W
12V 23W x4
12V 21W x4
12V 3.4W
12V 3.4W
12V 3.4W
12V 2.5A
12V 4W

Tubular, double-cradle
41° to either side
27°

102 mm

3.258-18 4PR, ribbed tread
3.508-18 4PR, universal tread
Telescopic fork

Swing arm

135 mm

80 mm

155~ 165 cc

SAE SW20

Dise brake

Interbal expansion, leading-trailing

180 x 30 mm
277 mm

* : Identical to KZ4000

® : France
@): Italy

K24008

-
i

Furukawa 12N 5.5-44
(12V 5.54H)

* *# «& &

££ #& & # © # &# © @

—

61 ~ 166 cc

t |

Internal expension, two leading

180 x 30 mm

Specifications subject to change without notice, and
may not apply to every country.

ENGINE PERFORMANCE CURVES 7

10 Ce 1,000)

10 (x 1000)

? 8 5

Crankshaft rar

6

Engine Performance Curves

US model

~ - (Qi-1j) w-By anbuoy
= re = in
i = pe = (4-duu6) vonduinsuag jang
a = = La
3 o wn o 3 =
et a ol = ie __2
]
a7 =
2
a
—
ri 4 |
5
oO
ify ent) 5-
g Lie
=
a
ri bs
3 i
: = a Ff bt a = =

dH inding euléuZ

:
d i
European model

8 RUNNING PERFORMANCE CURVES

Running Performance Curves

US model

Jt 4
)

European model

Driving Force kg

ADJUSTMENT 9

Adjustment

THROTTLE CABLES

There are two throttle cables, the accelerator throttle
cable for opening the butterfly valves and the decelerator
throttle cable for closing them, If the cable adjustment
is tod loose from ¢cniher cable stretch or maladjustment,
the excessive play in the throttle grip will mean adecly
in throttle response, especially al low rpm, Also, the
butterfly valves may not open tully at full throttle, On
the other hand, tf the cable adjusiment is too tiht, the
throttle will be too sensitive and hard to control, and the
idling speed will be too high,

@Screw in fully the lock nuts and adjusting nuts at the
upper end of the throtile cables so as to give the
throttle vip plenty of play,

nat Miits!

e}

*lurn back the decelerator throttle cable adjusting nut
3 turns, There must still be play in the throttle grip;
if there is mot, loosen the lack nut at the lower end of
the decelerator throttle qible, turn the adjuster to
create a small amount of play, and retighten the lock
nul,

®Jurn back the accelerator throttle cable adjusting nut
until just where the throttle grip play ts virtually gone,
and tighten the lock nul,

#/urn inthe decelerator throttle cable adjusting nut until
the desired amount of throttle gop play is obtained,
lighten the lock nut,

CARBURETORS ('74~'77 Model)

Although some internal carburetor parts can be adjust-
ed by replacement, repositioning, etc,, these adjustments
are covered in the Maintenance Section of this manual,
The following procedure covers the idling adjustment,
which is the adjustment necessary in periodic mainte-
nance and whenever the idling setting has been disturbed,
This procedure also includes the necessary steps for
obtaining proper carburetor synchronization,

When the idling speed is loo low, the engine may
stall, and when the idling speed is too high, the fuel
consumption becomes excessive, and a resulting lack of
engine brake may make the motorcycle difficult to
control, Poor carburetor synchronization will cause
unstable idling, sluggish throttle response, and reduced
engine power and performance,

The following procedure consists of four parts: pre-
liminary checks, preliminary adjustment [sometimes
necessary), idling adjustment, and carburctor synchro-
nivalion,

Preliminary Checks
@/n order to oblain correct idling adjustment, first check
and then correct, if necessary, the following:
Valve clearance (Pp. 14)
Engine oil (Pg. 181)
Spark plugs (Pe, 12 )
lenition timing (Pe. 12 )
Cylinder compression (Pe, 114)
Preliminary Adjustment

lf the engine idling is especially rough, it may be
necessary to make the following adjustment before
making the idling adjustment:

10 ADJUSTMENT

With the carburetors removed (Pg. 28, cable removal
not necessary), change the position of the pulley stop
screw if necessary so that the pulley rotation is stopped
at the point where the butterfly valves are parallel to
the carburetor bore. Tighten the lock nut after alter-
ation of the screw position.

4

e@lnstall the carburetors (Pg. 29), and check the throttle
grip play (Pg. 9).

Idling Adjustment

@Start the engine, and warm it up for 5 minutes.

@Back out the idling screw until the engine is at the
lowest rpm that it turns over smoothly.

_——
N - ae | —

®Turn both pilot screws to where engine rpm is highest.
In this time, pilot screw opening is 1% turns from 0
throttle open.

eAdjust idling speed to 1,100 ~ 1,300 rpm by turning
the idling screw.

@See if the engine rpm rises when the pilot screw po-
sitions are altered. If it rises, repeat the last three steps.

@Screw in each pilot screw 1/16 turn after the highest
idle position has been determined.
e@Turn the throttle grip a few times to make sure that
the idling speed does not change. Readjust if necessary.
NOTE: With the engine idling, turn the handlebar to
either side. If handlebar movement changes idling speed,
then the throttle cables may be improperly adjusted or
incorrectly routed, or else they may be damaged. If cable
adjustment does not clear up the problem, find the cause
and repair it,

Carburetor Synchronization
@Remove the vacuum plugs from each carburetor, and

attach the vacuum gauge and adapter (special tools),

eWith the engine running at idling speed, close down the
vacuum gauge intake valves until gauge needle flutter
is less than 3 cm Hg. Normal vacuum gauge reading
is 22~ 27cm Hg.

elf there is a difference ot more than 1 cm Hg between
the two gauges, stop the engine, remove the fuel tank
(Pg. 28), and use the balance adjuster (special tool)
on the balance adjusting screw to alter screw position
to where the difference in readings is below 1 cm Hg.
Run the engine with the fuel left in the float bowls,
When the screw is properly positioned, tighten the lock
nut, stop the engine, and install the fuel tank (Pg. 28).

eWith the engine running, turn both pilot screws so that
the vacuum gauge reading ss 22~ 37 cm Hg, and then
turn cach pilot screw in 1/16 turn,

eDetach the vacuum gatiges, and screw in the vacuum
plugs,

*Adjust the id
idling screw,

ia set of vacuum gauges 6 not available, carry out

the following steps for carburetor synchronization,

Listen to exhaust noise, and place your hands al the
rear of the mufflers to feel exhaust pressure,

ing speed to 1,100~ 1,300 rpm with the

elf there is a difference in noise or exhaust pressure
between the cylinders, stop the engine, remove the fucl
tank (Pa. 28), and use the balanee adjuster (special
tool) an the balance adjusting screw lo aller screw po-
sition ta where the difference is minimized, Run the
engine with the fuel left in the float bowls, When the
screw 14 properly positioned, tighten the lock nut, stop
the engine, and install the fuel tank (Pg. 25).

ADJUSTMENT 11

@Adjust the idling speed to 1,100~ 1,300 rpm with the
idling screw.

CLUTCH

Stretching of the clutch cable causes the clutch lever
to develop excessive play. Too much play will prevent
the lever from fully disengaging the clutch and will result
in shifting difficulty and possible clutch or transmission
damage, Most of the play must be adjusted out, but a
small amount has to be left so that the clutch release
lever will function properly,

Besides cable stretch, clutch plate wear also causes

the clutch to go oul of adjusiment, This wear causes
ihe play between the push rod and the adjusting screw
gradually to diminish until the push rod touches the
adjusting screw. When this play is lost, the clutch will
not engage fully, causing the clutch to slip,
NOTE: Even though there is the proper amount of play
at the clutch lever, clutch lever play alone cannot be
used to determine whether or not the clutch requires
adjustment,

The adjustment procedure which follows compensites
for both cable stretch and plate wear,
eSlide up the dust cover off the adiusting mul al tie

center of the clutch cable,
eScrew in fully the lock nut and adjusting mut at the
center of the clutch cable to give the cable plenty of
play.

| Adjustin g, Mut

ail,
hese ¥

1
1

®Loosen the lack mul at the eluteh lever just enoueh 39
that the adjuster will turn freely, and then turn the
adjuster to make a 5~6 mm gap belween the adjuster
and lock nut,

12 ADJUSTMENT

*Remove the clutch adjusting cover,
*Loosen the lock nut, and back out the clutch adjusting
screw 3 or 4 turns.

a % —
| Aan

+

Turn in the adjusting screw to where it becomes sudden-
ly hard ta turn, This is where the clutch begins to
engage,

*Back out the adjusting screw / turn from that point,
and tighter: the lock nut,

@Jake up all the cable play with the adjusting mut at the
center of the cable, and then tighten the lock nut, Slide
the dust cover back down,

®7urn the adjuster at the clutch Jever oo that the clutch
lever will have 2~3 mm of play as shown in Fig, 15,
and then tighten the lock nut,

*Replace the clutch adjusting cover.

SPARK PLUGS
Spark plug electrode wear will widen the gap and
cause missing and difficulty in starting. Too narrow a
gap as a result of maladjustment will also result in poor
performance since the small gap will produce only a
weak spark,
®Remove the spark plugs using a spark plug wrench.
@Clean the spark plug preferably in a sand-blasting
device, and then clean off any abrasive particles. The
plug may also be cleaned using a high flash-point
solvent and a wire brush or other suitable tool.
®Measure the gap with a wire-type thickness gauge. The
gap should be 0.7 ~0.8 mm; if it is not, bend the outer
electrode with a suitable tool to obtain the correct gap.

®lighten the spark plugs into the cylinder head with
2.5~ 3.0 ke-m (18.5~ 22.0 (t4bs) of torque,

IGNITION TIMING
Incorrect ignition timing can cause poor performance,
knocking, overheating, and serious engine damage, Pe-
riodic adjustment will be necessary lo compensate for
wear of parts, and the ignition timing must be checked
whenever ignition related parts have been disassembled
or replaced,
Correct ignition timing is achieved by first obtaining
the correct maximum contact breaker point gap and then
adjusting the position of the adjusting plate, Often the
first step returns the timing very close to the correct
original setting, Once the timing has been adjusted, it
may be checked for accuracy by the use of a strobe light.
@Leaving the ignition switch turned off, turn the engine
stop switch to one of the OFF positions,

®Remove the contact breaker cover.

*#Using a 17 mm wrench on the crankshall, turn the
engine until the contact breaker points are at their
widest opening,

@Determine the size of the point gap with a thickness
gauge, The proper gap is 0.3 ~ G4 mm.

@lf the gap is incorrect, loosen the contact breaker base
screw, open the points using a slot screwdriver on the
contact breaker base pry point, and insert a blade thick-
ness of 0.35 mm between the points, Remove the slot
screwdriver, lighten the contact breaker base screw, and

remove the blade(s), Again turn the crankshaft, and
recheck the maximum point gap,

®7urn the crankshaft so that the “F" mark on the timing
advancer is aligned with the timing mark as shawn in
Fig. 19,

Connect an ohmmeter set to the Rx | range across the
contact breaker points by securing one lead to chassis
ground (such as the crankcase) and attaching or holding
the other lead firmly on the contact breaker spring or
to the contact breaker lead,

@Loosen the contact breaker plate screws (3) just enough
to allow the plate to move,

eUsing a screwdriver on the contact breaker plate pry
point, turn the plate until the contact breaker points
dre just al the point of opening, The ohmmeter needle

ADJUSTMENT 13

slarts to rise when the points just begin to open, At
this point, tighten the contact breaker plate screws (3).

®7Turning the crankshaft counterclockwise, check to see
if, when the needle jumps, the “F” mark is aligned with
the timing mark. If not, readjust.

@Check the point gap after ignition timing adjustment.

*Disconnect the ohmmeter leads, and turn the engine
stop switch back to the RUN pasition,

eConnect up a strobe light in the manner prescribed
by the manufacturer in order to check the ignition
timing under operating conditions, One example is
shown in Fig, 22.

Ignition Timing Test

1. lenition Coil
2. Spark Plug Cap

3. Strobe Light

eStart the engine, and direct the light at the timing
mark. At idling speed the timing mark and the “F"
mark on the timing advancer must be aligned for
correct low rpm ignition timing, At 3,000 rpm or
higher the timing mark and the pair of lines on the
timing advancer as shown in Fig. 23 must be aligned
for correct high rpm ignition timing. If both low and
high rpm ignition timing are incorrect, adjust the timing
as just explained, If either low or high rpm ignition

14 ADJUSTMENT

liming is correct but the other is nol, examine the
timing advancer mechanism (Pg. 166).

The most precise means to sel ihe maximum point
gap is to use a dwell angele tester instead of a thickness
gauge, I! oa dwell angle tester is used lo sel the gap,
substitule the following steps for the first five sleps in
the above procedure:
eRemove the contact breaker cover.
®Conncct the dwell angie tester—lead to chassis ground

fwich 2s ihe frame of crankcase) and the * lead to the
contact breaker spring or some exposed parl of the
contact breaker lead,

*lf a dwell angle tester calibrated in degrees ts used,
turn the selector knob to the lowest cam lobe setting.

eStart the engine, and let it idle,

@Note the reading on the tester, The dwell angele specr
fication is 185~ 195° fora tester calibrated in degrees
and 5] ~ 54 % for one calibrated in percentage. If the
lester selling is for more than one cam lobe, the reading
on the tester must be multiplicd by the cam lobe
number lo obtain the correct dwell angle,

#lf the dwell angle is not the same as the specification,
loosen the contact breaker base screw ilist enough so
thal a slot screwdriver at the contact breaker pry point
will be able to change the gap, adjust the gap until the
dwell angle specification is obtained, aod then tighten
the screw, :

®Stop the engine, disconnect the tester, and replace the
contact breaker cover,

NOTE: The dwell angle is the angular range for which
the contact breaker heel is off the cam lobe allowing the
current to flow to the ignition coil primary winding.

VALVE CLEARANCE

Valve and valve seal wear decreases valve clearance,
upsetting valve timing. If valve clearance ts left unadjust-
ed, the wear will eventually cause the valves to remain
partly open, which lowers performance, burns the valves
and valve seals, and may cause serious engine damage,

Valve clearance for each valve should be checked and,
if incorrect, adjusted in accordance with the periodic
maintenance chart (Pg. 180) and anytime that clearance
may have been affected by disassembly,

When carrying out adjustment, be caurclul to adjust
within the specified clearance. Adjusting to a. larger
waluic will both distur valve timing and cause engine
rose.

NOTE: Valve clearance must be checked when the
engine is cold,
eRemove the contact breaker cover,

@Remove the valve clearance adjuster plugs (4) and the
cylinder head cover caps (2).

eUsing a 17 mm wrench, turn the crankshaft counter-
clockwise while watching the movement of the inlet
valve (the valve to the rear) on the right side. When the
valve has just finished opening and closing (moving
downward and retuming upward), turn the crankshaft
in the same direction (counterclockwise) for about
another 44 turn until the “T" mark (the line adjoining
the “T") on the timing advancer aligns with the timing
mark.

@AL this crankshaft position, the piston in the right
cylinder is at the end of its compression stroke such
that the inlet and exhaust valve for the right cylinder
can be checked for clearance and then adjusted if
necessary, The correct clearance lor the inlet and
exhaust valves is 0.10~0,15 mm,

eCheck the valve clearance by slipping a 0.13 mm thick-
ness gauge blade between the rocker arm and the tip
of the valve stem, If the clearance is correct, there will
be a sight resistance as the blade is moved,

ADJUSTMENT 15

@lf the valve clearance is incorrect, loosen ils rocker

shaft lock nut, and turn the shaft with a screwdriver
towards (+) for extra clearance. Slip the thickness
gauge blade between the valve and rocker arm, and turn
the rocker shaft towards (—) so that the valve and
rocker arm are separated only by the blade. Pull out the
blade, and tighten the lock nut with 2,5 ~ 3.0 ke-m
{18~22 (t-lbs}) of torque while using the valve clearance
adjuster (special tool) to keep the rocker shaft from
luming. Recheck the clearance, and readjust if

necessary.

NOTE: When adjusting valve clearances, always keep
the rocker shaft punch mark on each shaft positioned
inward facing the (+) (—) marks,

®After finishing with the right cylinder valves, turn the
crankshalt counterclockwise one full wrn so that the
“T° mark again aligns with the timing mark, Check
the heft cylinder valves, and adjust if necessary.
@Replace the parts which were removed,

CAMSHAFT CHAIN

Camshaft chain and chain guide wear causes the chain
to develop slack, which will cause noise and may result
in engine damage. To keep the chain from making noise,
Periodic adjusiment is necessary in accordance with the
periodic maintenance chart (Pg. 180). However, if the
adjustment fails to keep the chain from making noise,
the chain guides have probably worn past the service
limit and will need to be replaced,

16 ADJUSTMENT

eRemove the contact breaker cover,

eRemove the chain tensioner cap and O ring.

®Turn the crankshaft counterclockwise while watching
the push rod (in the center of the push rod guide) move
in and out, Continue turning the crankshaft counter-
clockwise until the push rod again reaches the inner
most position, and then stop,

CAUTION: Don't turn the crankshaft backwards (clock-

wise), Turning the crankshaft backwards may cause im-

proper adjustment,

SLoosen the lock nut, and screw in the push rod guide
until the ends of the push rod guide and push rod are
flush,

CAUTION: Be sure that the ends are flush, If the push

rod guide is overtightened so that the push rod sticks out

even only 0.5 mm, the tensioner or chain may become
damaged,

®lighten the lock nut, and replace the chain tensioner
cip and O ring.

@®Replace the contact breaker cover,

STEERING

For safety, the steering should always be kept ad-
justed sy that the handlebar will turn freely but not
have excessive play.

lf the steering is loo tight, it will be difficult to tum
ihe handiebar quickly, the motorcycle may pull to one
side, and the steering stem bearings may become
damaged, !{ the steering is too loose, the handlebar
will vibrate, and the motorcycle will be unstable and
difficult to sleer in a straight line,

To check the steering adjustment, first place a stand
or block under the engine so that the frant wheel is
raised off the ground. Push the handlebar lightly to
cither side; if it continues moving under ils own momen-
tum, the steering is not too tight. Squatting in front
of the motorcycle, grasp the lower ends of the front
fork at the axle, and push and pull the front end back
and forth: if no play is felt, the steering is not too loose.

@#Pul the motorcycle up on its center stand, and jack
or prop up the engine so that the front wheel will
be off the ground,

®Loosen the steering stem head boll and the clamp bolt,

elising the stem nut wrench (special tool), turn the
steering stem lock nut down (clockwise) to tighten
ihe slecning or up (counterclockwise) to loosen iL

Stem Nut Wrench
a 57001-134

aera to 2 Nut
— a r 3 ‘

*Tighten down the steering stem head bolt with 5,5 kg-m
(40 ft-lbs) of Lorque,

eTighten the clamp bolt with 1.6~ 2.2 kgm (11.5~
16.0 ft-lbs) of torque.

®@Loosen the lower clamp bolts on the left and right
shock absorbers to let the tubes reseat themselves,
and then tighten the bolts with 2.0 ~ 3.0 kge-m (14.5
~ 27 ft-lbs) of torque.

i

eCheck the stecring again, and readjust if necessary.
‘

WHEEL BALANCE
To improve stability and decrease vibration at high
speed, the front and rear wheels must be kept balanced,
Check and balance each wheel as follows;
eRemove the wheel (Pgs. 72, 74, 77).
eCheck that all the spokes are tightened evenly,
eSuspend the wheel so that it can be spun freely,
e5pin the wheel lightly, and mark the spoke al the top
when the wheel stops.
e@Repeal this procedure several times, If the wheel stops
of its own accord in various positions, it is well balanced.
eHowever, if the wheel always stops in one position,
attach a balance weight loosely to the marked spoke,

eRotate the wheel 4 turn, and see whether or not the
wheel stops in its new position. If it does, the correct
balance weight is being used,

elf it does not, try other balance weights until the wheel
stays in positian when rotated 4 turn,

@Rotate the wheel another i turn and then another
44 turn to see if the wheel is correctly balanced,

@Repeat the entire procedure as many limes as necessary
to achieve correct wheel balance, and then clamp on
the balance weights firmly using pliers.

eMount the wheel back onto the motorcycle (Pgs. 72,
74, 77).

NOTE: Balance weights are available from Kawasaki
Dealers in 10, 20, and 30 gram sizes, An imbalance
of less than 10 grams will not usually affect running
stability.

ADJUSTMENT 17
FRONT BRAKE LEVER(Only on K 24000)

Disc and disc pad wear is automatically compensated
for and has no affect on brake lever action, However,
the brake lever may occasionally require adjustment duc
to wear inside the lever assembly itself or in case of lever
disassembly. Excessive play must be taken up to keep
the lever from vibrating, but enough play must be leit
to ensure a full braking stroke,
eStraighten the part of the washer that is bent over the

side of the adjusting bolt lock nut,
@Loosen the lock nut, turn the adjusting bolt a fraction
of a turn so that lever play is under 5 mm,and retighten

the lock nut with L&~ 2.3 kem (14~ 16.5 ft-lbs) of
Lorgue,

eBend back part of the washer over the side of the lock
Mut,

FRONT BRAKE (Only on KZ4 005)

Brake lining wear, drum wear, and cable siretch cause
the brake to go out of adjustment, increasing lever play
and decreasing braking effectiveness, Brake adjustment
to compensate for this consists of three successive adjust-
ments: cam lever angle, brake shoe synchronization, brake
lever,

If brake drag is detected during brake adjustment,
or if the brake does not return lo its rest position
quickly upon release, disassemble the brake (Pg. 73 }
and inspect for wear or damage (Pg. 145).

On the oulside of the front brake panel there is a
brake lining wear indicator, Whenever the indicator
has gone past USABLE RANGE, the brake shoes must
be replaced immediately and the other brake parts
examined, Adjustment alone cannol compensate for
the wear of a brake worn past the usable range.

18 ADJUSTMENT

Cam Lever Angle

@When the brake is fully applied, the primary brake cam
lever should be at an 80~90° angle with the threaded
extension of the brake cable, at the same time as which
the secondary brake cam Jever should be parallel with
the primary brake cam lever. If they are nol, remove
the cam levers and then remount them at new positions
on the shafts to achieve the proper angle, of loosen the
lock nut and tum the conneeling rad to make the lwo
cam levers parallel,

CAUTION: Since a cam lever angle greater than 90°
reduces braking effectiveness, this adjustment should
not be neglected, When remounting the cam, be sure
that the position of the indicator on the serrated shaft
is not altered, The change in cam lever angle is caused
by wear of internal brake parts. Whenever the cam lever
angle is adjusted, also check for shoe drag and proper
lever operation, taking particular note of the brake lining
wear indicator position, In case of doubt as to braking
effectiveness, disassemble and inspect all internal brake
parts, Worn parts could cause the brake to lock or fail.

Brake Shoe Synchronization

ePut the motorcycle up on its center stand, and jack up
or prop up the engine so that the front wheel is off
the ground,

@Loosen the lock nut and tum the connecting rod one
turn in direction *A*, This procedure backs off the
secondary brake shoe so that it will not operate when

the primary shoe contacts the inside surface of the drum.

eWhile spinning the wheel lightly, turn in the adjusting
nut until the primary shoe just starts touching the
drum. When the shoe starts touching the drum, light
dragging can be felt or heard.

< i Eta #

eSpinning the wheel lightly, turn the connecting rod
in direction “B" until the secondary brake shoe just
starts dragging on the drum, and then tighten the lock
nut,

Front Brake Lever
@loosen the lock nut at the front brake lever, screw
the adjuster fully in, and tighten the lock nut,

elurn the adjusting nut on the lower end of the front
brake cable so that when the brake is fully applied,
there is 55 ~ 65 mm space left between the throttle
grip and the end of the brake lever.

45)

55° 65mm

REAR BRAKE

Brake lining and drum wear causes the rear brake
to go oul of adjustment, increasing pedal play and
decreasing braking effectiveness. Rear brake adjustment
lo compensate for this actually consists of three suc-
cessive adjustments: brake pedal position, cam lever
angle, and brake pedal travel.

If brake drag is detected during brake adjustment,
disassemble the brake (Pe. 78 ), and inspect for wear
or damage (Pg. 145). Also, if the brake pedal does
not relurn to its rest position quickly upon release,
inspect the brake for wear or damage.

On the outside of the rear brake panel there 15 a
brake lining wear indicator. Whenever the indicator has
gone past USABLE RANGE, the brake shoes must be
immediately replaced and the other brake parts ex-
amined, Adjustment alone cannot compensate for the
wear of a brake worn past USABLE RANGE,

Brake Pedal Position

eWhen the brake pedal is in ils rest position, it should

be 20~ 30 mm Jower than the upper surface of the
rivht front foot rest. If it is not, first loosen the
adjusting nut on the end of the brake rod to give
the brake pedal plenty of play,

®Loosen the brake pedal adjusting boll lock nut, tum
the adjusting belt to obtain the correct pedal position,
and tighten the lock nut,

ADJUSTMENT 19

Cam Lever Angle

eWhen the brake is fully applied, the brake cam lever
should come to an S0~ 90 angle with the brake rod.
if it does not, remove the cam lever, and then remount
it al a new position on the shalt for the proper angle.

CAUTION: Since a cam lever angle greater than 90°
reduces braking effectiveness, this adjustment should
not be neglected. When remounting the cam, be sure
that the position of the indicator on the serrated shaft
is not altered, The change in cam lever angle is caused
by wear of internal brake parts. Whenever the cam lever
angle is adjusted, also check for drag and proper pedal
operation, taking particular note of the brake lining wear
indicator position. In case of doubt as to braking
effectiveness, disassemble and inspect all internal brake
parts, Worn parts could cause the brake to lock or fail.

Brake Pedal Travel

@lurn the adjusting nut on the end of the brake rod so
that the brake pedal has 20~30 mm of travel from the
rest position to the fully applied position when the
brake pedal is pushed down lightly by hand,

£

20= 30m

MX AWASAK) °

=|

20 ADJUSTMENT

\_ Adjusting Nut

4%,

®Rotate the rear wheel to check for brake drag.
*Operate the pedal a few times to see that it returns bo
its rest position from the fully applied position im-
mediately upon release,

*®Check the rear brake light switch adjustment,

BRAKE LIGHT SWITCH

The front brake light switch of the KZ400D, mounted
in the stem base, operates hydraulically and is not ad-
justable. The front brake light switch of the KZ4005,
mounted on the front brake lever, is operated by simple
electrical contact and should not need adjustment,
However, the rear brake light switch, activated by a
spring attached to the brake pedal, requires periodic
adjustment to compensate for any change in spring
shape of tension,

Check the operation of the switch by turning on the
ignition switch and depressing the brake pedal, The
brake light should go on after 15 mm of pedal travel
or shortly before the brake pedal reaches the fully
applied position.

®Turn the switch adjusting nut up or down so that the
brake light will go on after the correct amount of brake
pedal travel, A higher switch position will make the
light go on after less travel,

CAUTION: To avoid damaging the electrical connections
inside the switch, be sure that the switch body does not
turn during adjustment.

DRIVE CHAIN

Chain and sprocket wear causes the chain to lengthen,
which results in power loss, accelerated chain and
sprackel wear, and increased noise, A lengthened chain
which is not adjusted properly may possibly be thrown
off the sprockets or break, A chain that has been
adjusted too tight will wear excessively and possibly
break.

To determine whether or not the chain requires
adjustment, first set the motorcycle up on its center
stand (on the side stand in the case of KZ4005S), rotate
the rear wheel to obtain the location of the least slack,
and measure the vertical movement midway between
the sprockets, If it is less than 15 mm or more than
30 mm (less than 10 mm or more than 25 mm in the
case of KZ4005), adjust the chain so that the vertical
movement will be about 20~ 25 mm (15 ~20 mm in
the case of KZ4005).

Fa

Chain Slack ( 53)

ia

'
Slack
CAUTION: A chain worn past the service limit (Pg. 139)
should be replaced. Such wear cannot be adequately
compensated by adjustment.
*Remove the clip, and loosen the nut at the rear end
of the torque link,

®Remove the axle cotter pin, and loosen the axle nut,

@Loosen the left and right chain adjuster lock nuts,
elf the chain is too tight, back out the left and right
chain adjuster bolts, and then kick the wheel forward
until the chain is too loose,

Chain Adjuster Bolts)

—i\

®lurn in the left and right chain adjuster bolts evenly
until the drive chain has the correct amount of slack.
To keep the chain and wheel aligned, the notch on the
left chain adjuster should come to the same swing arm
mark that the right chain adjuster notch comes to,

ADJUSTMENT 21

@Tighten both chain adjuster lock nuts, and then tighten
the coupling sleeve nut securely,

®Tighten the axle nut with 10~14 kg-m (72~101 ft-lbs)
of torque.

®Kotate the wheel, measure the vertical movement again,
and readjust if necessary.

®insert a new cotter pin through the axle nut and axle,

®Tighten the torque link rear nut with 2.6~3.5 kg-m
(19~25 ft-lbs) of torque, and replace the clip.

eCheck the rear brake adjustment (Pg. 19) and the
rear brake light switch adjustment (Pg. 20).

REAR SHOCK ABSORBERS
The rear shack absorbers can be adjusted to one of
five positions to suit riding conditions, They can be left
solt for average riding but should be adjusted harder for
high speed riding or riding on bad roads. Shock absorbers
adjusted either too soft or too hard adversely affect riding
comfort and stability.
®furn the adjusting sleeve on cach shock absorber to the
desired position with a hook spanner. The higher the
adjusting sleeve is positioned, the stronger the spring
tension, and the harder the ride,

@Check to see that both adjusting sleeves are turned
to the same relative position.

22 ADJUSTMENT

HEADLIGHT

The headlight beam is adjustable both horizontally
and vertically, If not properly adjusted horizontally,
ihe beam will point to one side rather than straight
ahead, Wf adjusted too low vertically, neither low nor
high beam will illuminate the road far enough ahead,
lf adjusted too high vertically, high beam will fail to
illuminate the road close ahead, and low beam will blind
ancoming drivers,

Horizontal Adjustment (Only on US model):

®lum in or out the small screw on the headlight rim
until the beam points straight ahead.

Vertical Adjustment:
*Loosen the headlight housing mounting bolts,

Horn Current Measurement
Harn Burton

seat

eMove the headlight up or down by hand to where the
vertical aim is correct,
®Jighten the headlight housing mounting bolts,

HORN

The horn contacts wear down after long use and will
need to be adjusted from time to time, Turning in the
adjusting screw compensates for contact wear, If satis-
factory hern performance cannet be obtained by this
adjustment when the rest of the electrical system is
functioning properly, the harn must be replaced, It
can not be disassembled,

CAUTION: Do not turn the adjusting screw in too far

since doing so will increase horn current possibly burning

out the horn coil,

#Disconnect the black horn leads, and connect an am-
meler in series to the horn circuit. The + ammeter
lead goes to the horn terminal lead and the — ammeter
lead to the remaining lead,

@Fully loosen the adjusting screw lock nul.

@Turn on the ignition key, and keep the horn button
pressed while turning the horn adjusting screw, Adjust
for the best horn sound while keeping the current
between 1.8~ 2.5 amperes,

@lighten the adjusting screw lock nut,
NOTE: The horn will not sound properly if itis mount-
ed incorrectly or if any cable or other part is touching it,

Black

Brown

Hearn

DISASSEMBLY 23

Disassembly

INTRODUCTION TO DISASSEMBLY
Detail has not been spared in this section in order that the motorcycle can be not only taken
apart but also put back together properly as well. Photographs, diagrams, notes, cautions, and
detailed descriptions have been included wherever felt necessary. Nevertheless, even a detailed
account has limitations; a certain amount of basic knowledge is also required for successful work.
Especially note the following:
(1) Force
Common sense should dictate how much force is necessary in assembly and disassembly.
If a part seems especially difficult to remove or install, stop and examine what may be causing
the problem. Whenever tapping is necessary, tap lightly using a plastic hammer. Use an impact
driver for screws — particularly for the removal of screws held by a locking agent in order to
avoid damaging the screw heads.
(2) Torque
The torque values given in this Shop Manual should always be adhered to. Either too little
or too much torque may lead to serious damage. Use a good quality, reliable torque wrench.
(3) Lubricant
Don’t use just any oil or grease. Some oils and greases in particular should be used only in
certain applications and may be harmful if used in an application for which they are not intended.
(4) Lubrication
Engine wear is generally at its maximum while the engine is warming up and before all the
rubbing surfaces have an adequate lubricative film, During assembly oil should be applied to
any bearing surface which has lost its lubricative film. Old grease and dirty oil should be
cleaned off, Deteriorated grease has lost its lubricative quality and may contain abrasive foreign
particles,
(5) Press
A part installed using a press or driver, such as a wheel bearing, should first be coated with
oil on its outer or inner circumference so that it will go into place smoothly.
(6) Oil Seals
An oil seal guide is required for certain oil seals during installation to avoid damage to the
oil seal lips. Before a shaft passes through an oil seal, apply a little oil on the lips to reduce
rubber to metal friction.
(7) Gasket
When in doubt as to the condition of a gasket, replace it with anew one. The fitting surfaces
around the gasket should be free of foreign matter and perfectly smooth to avoid oi! or com-
pression leaks.
(8) Edges
Watch for sharp edges, especially during major engine disassembly and assembly. Use a clean
piece of thick cloth when lifting the engine or turning it over.

ENGINE

Removal:

eWith the motorcycle on its center stand, place an oil
pan beneath the engine, and remove the cngine oil drain
plug and oil filter to drain out the oil. The drain plug “5
and oil filter may be replaced once all the oil has drain- ] j =
ed out or later during engine installation, a

mEs

EngineiOil\DrainiPlugese

a

24 DISASSEMBLY

@Remove the fuel tank (Pg. 28).

@Pull off the spark plug lead from cach spark plug,

@Disconnect the blue contact breaker lead from where
it connects to the blue ignition coil lead, loosen slightly
the straps (4) which hold the lead to the frame, and
slide the lead free from the frame.

@Unscrew the tachometer cable from the cylinder head
cover (KZ400D).

ePull off the right and left side covers,

eDisconnect the plugs (2) from their sockets under the
vollage regulator,

#Remove the starter lead from the starter relay terminal
(KZ400D),
®@Loosen the engine intake duct clamp for each carbu-

retor,
| } f 7 : —
& ‘ “ a 4 a 3 1 | az = ? /

a

a

i

@Loosen the clamp that connects cach air cleaner duct
to its carburetor, and slip it out of place.

eSlip the carburetors down and out of their ducts, pull
the carburetors free, and set them on top of the frame.

@eRemove the muffler collar nuts and lock washers (4
ea), and slide each mufiler collar off its cylinder head
suds,

@®Remove each rear foot peg to complete muffler re-
moval. Also, remove the muffler gasket from each
exhaust port.

@Check to see that the transmission is in neutral, then
take out the shift pedal bolt, and remove the shilt
pedal,

eRemove the left foot peg bolt, left foot peg, and side
stand spring,

eRemove the engine sprocket cover screws (4), and pull
the cover free from the crankcase.

eRemove the clip carefully from the drive chain master
link with pliers, remove the master link, and remove
the drive chain from the engine sprocket,

@Remove the bracket connecting the breather cover to
the frame.

@®Remove the breather cover bolts (4), and remove the
Cover,

@eRemove the rear brake light switch spring.

@Hold the rear brake light switch body steady, and turn
the adjusting nut counterclockwise until the lower
portion can be pressed inward,

ePressing inward on the lower portion of the adjusting
nut, push the switch up and out of its bracket.

. SEX
Adjustipa ones

fe

fs

@Remove the nuts from the engine mounting bolts (3),
and remove cach mounting bolt, Be careful not to
damage the threads upon removal, raising the engine
up a little as necessary, A spacer comes off each of
the rear bolts,

Engine Mountings

ed =o A,
(es

. Front Mounting Bracket
2, Front Mounting Bolt

. Rear Upper Mounting Bolt
4, Rear Lower Mounting Bolt

eRemove the left front engine mounting bracket,

@Loosen the clutch cable straps (2), slide the straps up,
and situate the engine sprocket cover so that the clutch
cable will not get damaged during engine removal.

@Lift up on the front of the engine, and then remove
it from the left side of the frame, top first and rear last,

Installation:
ePiace the engine into the frame the reverse of how
it was removed.

DISASSEMBLY 25

®Replace the left front engine mounting bracket, and
tighten first the upper bolt and then the lower with
2.0~2.8 kg-m (14.5~20 ft-lbs) of torque. Each bolt
has a lock washer. The clutch cable goes as shown in
Fig. 73.

eLifting the engine as mecessary so thal the mounting,
bolt threads do not get damaged, insert the engine
mounting bolts, Both -sar bolts run through a spacer
on the left side,

®Replace the lock washers and nuts with the spring side
of the nuts facing out, and tighten each nut with 3.4
~4.6 kg-m (25~33 ft-lbs) of torque.

NOTE: Some machines have one or more shims added
to the lower spacer, After the nuts are tightened to the

proper torque, check to see whether or not the spacer
takes up all the space. If mot, add one or more shims.

®Replace the rear brake light switch, and fit its spring
back in place.

®Apply liquid gasket if necessary to the breather cover
Oring groove to hold the Oring in place for installation,

26 DISASSEMBLY

®Replace the breather cover, and lighten its bolts with
1.8~ 2.3 kge-m (13 ~ 16.5 ft4bs) of torque. Each bolt
has a flat washer,

®Replace the breather cover bracket. Each bolt has a
lock washer.

®Fit the drive chain back on the sprockets with the ends
on the rear sprocket as shown in Fig. 76.

®Replace the chain master link with pliers. The direction
of the master link clip should be as shown in Fig. 77.

@Replace the engine sprocket cover using the shift shaft
oil seal guide (special tool) to protect the oil seal in the
cover, and tighten its screws, The wiring is routed in
front of the upper mounting bolt spacer.

=A

Wapen Mounting Bolt

ide |

' 2 \
§Shift Shaft OiliSeal Gu
2001-264 alll | -@

eSecure the clutch cable to the left down tube with the
Slraps,

efor each muffler, fit its gasket and the end of the
muffler into its exhatist port, and attach the muffler
lo the frame tightening its foot peg nut loosely. A
lock washer and flat washer go with the nut,

®Fit cach split keeper and collar back into place, and
tighten the collar nuts evenly to avoid an exhaust leak,
There is a Jock washer for each nut.

®Tighten the foot peg bolts securely.

@®Fit the side stand spring into place, and then secure
the left foot peg with its bolt,

@Replace the shift pedal so that its end matches the
level of the dynamo cover lower right screw,

“en

®Slip the carburetors back into place the reverse of how
they were removed, The throttle cables go along the
right side of the top tube.

eOnce the ducts are all properly fitted on the carbu-
retors, tighten all four clamps. Route the carburetor
tubes (4) to the rear through their guide,

®Reconnect the plugs (2) to their sockets under the
vollage regulator,

*Replace the starter lead on the starter relay terminal
(KZ400D).

@Replace the right and left side covers.

®Tighten the bottom end of the tachometer cable into
its place in the cylinder head cover (KZ400D).

®Run the contact breaker lead through its straps (4),
and connect it to the blue ignition coil lead. Tighten
the straps.

eConnect cach spark plug lead onto its spark plug,
@lnstall the fuel tank (Pg. 28 ).,

@Make sure the O rings are in place, and replace the
oil filter and drain plug. Tighten the oil filter with
1.5 ~ 2.0 kg-m (11 ~ 14.5 ft-lbs) of torque and the
drain plug with 2.7 ~ 3.3 kem (19.5 ~ 24 ft-lbs),

Drain Plug Oil Filter 83)

i!
1
i’

“0” Rings

eF ill the engine with oil, check the level (Pg.181), and
add more if necessary,

eCheck the drive chain slack, and adjust (Pg. 20 ) if
necessary,

@Adjust the rear brake light switch (Pg. 20).

AIR CLEANER ELEMENT

Removal:

*Pull off the left side cover.

@Remove the air cleaner housing side cover screw, and
pull off the side cover, The screw has a lock washer
and flat washer,

DISASSEMBLY 27

@Pull out the clement,

Installation Note:
®Replace the element so that the element holes match
the air cleaner ducts,

OlL FILTER

Removal:

eWith the motorcycle on its center stand, place an oil
pan beneath the engine, and remove the oil filter,

Installation:

@Make sure that the O ring is properly in place, and
replace the oil filter tightening its bolt with 1.5~ 2.0
ke-m (11 ~ 14.5 ft-lbs) of torque.

®Pour the oil back in, check the level (Pg. 181), and
add more if necessary,

Disassembly:

While holding the element steady, turn the bolt to work
the element free.

®Remove the flat washer, spring, and pull the filter base
off the bolt,

28 DISASSEMBLY

faa

ene eeS 86)

4
Washer Spring: “O Ringé

on

coun

r

*7o remove the bypass valve, drive out the pin, and
drop out the spring and piston.

Assembly:

@Fit in the piston and spring, and drive in the pin while
pressing the spring down,

@Replace cither O ring with a new one if deteriorated
or damaged.

e@Fit the filter base on the bolt, and replace the spring
and flat washer.

®Holding the clement steady, turn the bolt to work the
clement into place. Be careful that the element
grommets do not slip out of place,

MUFFLERS (Only on KZ400D)
Removal (per muffler):

@®Remove the muffler collar nuts and lock washers, and
slide the muffler collar off its cylinder head studs.

= c
?— §

@Remove the rear foot peg to complete muffler removal.
Also, remove the muffler gasket from the exhaust port,

Installation (per muffler):

@Fit the gasket and the end of the muffler into the
exhaust port, and attach the muffler to the frame
lightening the foot peg nut loosely, A lock washer
and flat washer go with the nut,

*Fit the split keeper and collar back into place, and
lighten the collar nuts evenly to avoid an exhaust leak,
There is a lock washer for each nut,

®@lighten the foot peg bolt securely.

MUFFLERS (Only on KZ4005)

Removal:

®Remove the muffler collar nuts and lock washers, and
slide the muffler collars off its cylinder head studs
(Fig. 83).

@Remove the right rear foot peg to complete mufflers
removal. Also, remove the muffler gaskets from the
exhaust ports.

Installation:

@Fit the gaskets and the end of the mufflers into the
exhaust ports, and attach the muffler to the frame
tightening the right foot peg nut loosely. A lock
washer and flat washer go with the nut.

*Fit the split keepers and collars back into place, and
tighten the collar nuts evenly to avoid an exhaust leak.
There is a lock washer for each nut (Fig. $9).

FUEL TANK

Removal:

eTurn the fuel tap to OFF, slide down the hose clamps,
and pull the fuel hoses (2) off the tap.

@Uniock the seat, and swing it open,

@Unhook the rubber retaining band, and pull the fuel
tank off towards the rear,

Installation:

@®Replace the fuel tank, and hook its retaining band,

@Fit the fuel hoses back onto the fuel tap, and slide
the clamps back into place,

@Push the seat back down,

CARBURETORS
Removal:
@lake off the right and left side covers.

@lurn the fuel tap to OFF, slide down the hose clamps,
and pull the fuel hoses (2) off the tap.

®Loosen the engine intake duct clamp for each carbu-
retor.

*Loosen the clamp that connects each air cleaner duct
to its carburetor, and slip it out of place,

the right side of the motorcycle,

*Screw in fully the lock nuts and adjusting nuts al the
upper end of the throttle cables so as to give the
throttle grip plenty of play.

*Screw one ol the cable adjusters out of its bracket,
slip the tip of its inner cable out of the pulley, and
then do the same with ‘the other throttle cable to
complete carburetor removal,

Installation:

elf necessary, change the position of the pulley stop
screw $0 that the pulley rotation is stopped at the
point where the butterfly valves are parallel to the
carburetor bore, Tighten the lock nut after alteration
of the screw posilion,

DISASSEMBLY 29

@Fit the tip of the accelerator throttle cable into the
rear catch in the pulley, and screw its adjuster down
into the bracket all the way,

- _ = ; | ‘ G3
Tora ihrottle.Cable . a

1
4 Y

*Fit the tip of the other cable into the other catch,
and lift its adjuster onto the bracket turning the
throttle grip at the same time if necessary.

eCenter each adjuster in its place in the bracket, and
lighten the lock nuts,

@Slip the carburetors back into place the reverse of how
they were removed,

@#QOnce the ducts are all properly fitted on the carbu-
retors, tighten all four clamps.

®*Route the carburetor tubes (4) to the rear through
their guide.

30 DISASSEMBLY

®Fit the fuel hoses back onto the fuel tap, and slide
the clamps back into place,

@Replace the right and left side covers.

eAdjust the throttle cables (Pg. 9).

Upper Chamber and Float Chamber Disassembly:

@Remove the upper chamber screws, and take off the
carburetor cap 2).

@Pull our the vacuum piston (13), and take out the vacuum
piston gasket (12,

®7o remove the jet needle 15), take out the screw 14 and
drop out the jet needle,

®lTo remove the air jets, remove the screw (16) and lock
washer (17) and take out the plate 18 and plate gasket
19. The main air jet 20 and slow air jet 21) may be
removed with a small slot screwdriver.

®Remove the screws (4) $0, and pull off the float
bowl a7.

@Remove the jet keeper 45).

@#Push out the float pin 47, remove the float 46), and
pull out the float valve needle (37 ,

®To remove the float valve seat 37), remove its screw
and retainer (35), and pull it out,

@]o remove the main jet 44 and needle jet 42), pull out
the main jet and then drop out the needle jet.

@lo remove the starter jet 41), use a large slot screw-
driver,

@To remove the pilot jet (3% and slow jet 40, pull out
the pilot passage plug 3x3 , and remove them using a
small slot screwdriver,

Upper Chamber and Float Chamber
Assembly Notes:

I. Replace any deteriorated gaskets or rubber parts
(vacuum piston gasket, air jet gasket, valve seat O
ring a4, Upper main jet groove O ring 43), pilol passage
plug, and float bowl ring 33) for new ones,

2. Be sure that the float 15 replaced facing the right
way (Pg. 103 Fig. 388).

3. Replace the jet keeper as shown in Fig. 96, and
then screw on the float bowl. The jet keeper is used
to keep the main jet and pilot passage plug in place.

Linkage Mechanism and Starter Plunger Unit
Disassembly:

@Remove the left carburetor from the mounting plate
(7), taking out its screws (2) (7) 8 and slipping it out of
its balance adjusting screw connection and choke lever
linkage.

#®Separate the right carburetor from the mounting plate,
removing its screws (2).

@To disassemble the linkage mechanism, first straighten
back the linkage bar washer sides which are bent over
the bolt, and remove the bolt #1, washer @®, spring
g), and pusher 7.

@Remove the linkage bar C rings @ and washers 5),
and pull off the bar (1).

#Remove the C ring 73 from the pulley screw é2 , and pull
off the flat washer 72 , plastic washer §5), pulley 7) ,
and plastic washer (68) .

#Remove the cable bracket 7 and then the pulley
spring (64) .

®To disassemble the starter plunger unit, unscrew the
cap (7), pull out the unit, and slide off the plunger ii,
Removal of the right carburetor starter plunger unit
requires removal of the cable bracket,

Linkage Mechanism and Starter Plunger Unit
Assembly Note:

®7To mount the left carburetor, first fit the choke linkage
together, connect the balance adjusting screw con-
nection ‘8 with the bracket between the washers, and
fit the spring between the carburetors. Then fit the
choke linkage in place, and replace the mounting
plate screws, Use a non-permanent locking agant
on each mounting plate screw.

ROCKER ARMS

Removal:

@Remove the fuel tank (Pg. 28).

@®Remove the bracket connecting the breather cover to
the frame.

Carburetor
1. Mounting Plate
2. O Ring
3. Linkage Shaft
4. Screw
5. Lock Washer
6, Rubber Cap
7, Cap
&. Washer
9, Spring
10, Plunger Shaft
I]. Plunger
2. Gasket
13. Cap & Vacuum Piston
I. Screw
15, Jet Needle
IG, Screw
17, Lock Washer
Id. Plate ~~
19, Gasket OY <<
20, Main Air Jet 76)75) .@ s
21. Slow Air Jet ; 9 q)
22. Clip (76) (74)
23, Fuel Hose
24, Clip
35, Vacuum Plug 47, Float Pin
26, Washer 48, Drain Plug
27, Pilot Screw 49. O Ring
28. Spring 50, Screw
29, Washer 51. Idling Screw
30, Oring 52. Washer
31. Carburetor Tube 53. Plate
32, Clip 54, Screw
33. O Ring 55, Lock Washer
34. O Ring 56, C Ring
35, Retainer 57. Clip
36, Screw 58, Carburetor Tube
37. Float Valve Seat 59, Clip
& Valve Needle 60. Spring
38. Pilot Passage Plug O61, Washer
39, Pilot Jet G2, Pulley Screw
40, Slow Jet 63, Nut
4], Starter Jet 64, Pulley Spring
42, Needle Jet 65, Plastic Washer
43, 0 Ring 66. Lock Washer
44, Main Jet G7, Screw
45, Jet Keeper 68, Pulley Stop Screw
46, Float GY, Nut

G7)

~~

. Cable Bracket
. Pulley :
. Washer

. C Ring

4, Linkage Bar

Washer
C Ring
B ar

Pusher
Spring
Washer

. Boll
. Balance

Adjusting Screw

83.
B41.
85.
6.
87.
BS.
89.

0),

He

Pa

(00) (i)

-

fi

0)

Washer

Washer
Spring
Wave Washer
Screw

Screw

Collar

Lever

DISASSEMBLY 31

91. Lever

92. Lock Washer

93. Nut

1, Choke Linkage Rod

95, Screw

96. Spring

07. Float Bowl

Q6. Adjusting Screw Connectio

32 DISASSEMBLY

®Remove the breather cover bolts (4), and slip the cover e@Pull the leads off the spark plugs, and remove the
off the cylinder head cover and out of the way, spark plugs.

@Unscrew the tachometer cable from the cylinder head ®Remove the tachometer gear from the cover (KZ400).
cover (KZ400D). eRemove the contact breaker cover, turn the crankshaft

@Remove the stud nuts (8), and pull off the cylinder such that the timing advancer “T” mark aligns with the
head cover, The cover has four O rings. timing mark, and then replace the contact breaker cover,

®Remove the cylinder head cover caps (2). e®Apply liquid gasket to the cylinder head cover O ring

®Kemove the nut from each shaft, and remove the plates fitting surface if necessary to hold the O ring to the
(2). cover, Check that all O rings (4) are in place.

Rocker Shaft

a

®/o remove a rocker arm, wrap a thick piece of cloth @Place the cylinder head cover on the cylinder head, and
around the end of the shaft, and pull the shaft out replace the nuts (8). Tighten the nuts in the sequence
with pliers, shown in Fig. 103, tightening first each nut to 1.5 kg-m

(11 ft-lbs) of torque and then to 2,5 ~ 3.0 kg-m
(18 ~ 22 ft-lbs).

Cylinder Head Cover Tightening Order

Installation:

@Daub a litte oi] on each shaft O fing, run each shaft
into the cover and through its rocker arm. The large
contact surface of the rocker arm rides on the cam,
Iurn each shalt such that the punch mark faces in,

®Replace the cylinder head cover caps (2).

@Apply a small amount of heat durable grease to the
tachometer gear, insert the gear, and reconnect the
cable to the cylinder head cover (KZ400D).

®*Replace the spark plugs, and connect cach spark plug
lead onto its plug.

@Apply liquid gasket if necessary to the breather cover
O ring groove to hold the O ring in place for installation,

®Replace the breather cover tightening its bolts (4) with
1.8~ 2.3 ke-m (13~ 16.5 ft-lbs) of torque. Each bolt
has a flat washer,

- @Replace the breather cover bracket, Each bolt has a
lock washer,

@install the fuel tank (Pg. 28).

®Replace the plates and each shaft nut. #Adjust the valve clearance (Pg. 14),

CAMSHAFT

Removal:

®Remove the fuel tank (Pg, 28).

®Kemove the bracket connecting the breather cover to
the frame.

fz

7 a
“, .
Breather, Covers

all

#Remove the breather cover bolts (4), and slip the cover
off the cylinder head cover and out of the way,
*Unscrew the tachometer cable from the cylinder head
cover (KZ400D).

@Remove the stud nuts, and pull off the cylinder head
cover, The cover has four O rings,

#Remove the chain tensioner cap and O ring,

#Remove the chain tensioner screws, and pull out the
entire tensioner assembly,

eed! / | | | | ,

eKemove the contact breaker cover and gasket,
@Remove the camshaft sprocket bolts (2). Use a 17mm
wrench to lurn the crankshaft.

@Slide the sprocket off its position on the camshaft, and
slip the chain off the sprocket,

DISASSEMBLY 33

®Remove the camshaft and sprocket. Use a screwdriver
io keep the chain from falling down into the cylinder
block,

Installation:

*Place a cylinder head holding plate (special tool) on
both sides of the cylinder head, and tighten both in
place using the stud nuts (8),

: ‘ ae a
ae 7 sylinder He ad Holding piste |
2001
eSct ra seiretael on the camshaft near where it fits.
The arrowed side of the sprocket faces the right side

of the engine.

#Run the camshaft through the camshaft chain from
the right side of the engine, and fit the chain on the
sprocket,

@eUsing a 1/7 mm wrench on the crankshaft, turn the
engine to where the timing advancer “T” mark (the
line adjoining the “T”) aligns with the timing mark.
Next, turn the crankshaft counterclockwise exactly 90°
(4% turn). Verify crankshaft position by checking that
the timing mark ts aligned with the timing advancer as

shown in Fig, 110.

34 DISASSEMBLY

®lurn the sprocket such that the arrow which has no

Gamshate: Liming (D) letter adjoining it points to the front of the engine
(points parallel to the cylinder head fitting surface),
—, sip the chain back on the sprocket; and fit the
© sprocket up into place (the bolt holes will nol be
aligned at this time),

NOTE: The camshalt chain must be fitted with the

crankshalt, sprocket, and camshaft positioned as just

described, Otherwise, the valve timing will be incorrect,

The reason for fitting the chain on the sprocket before

turning the crankshaft is to avoid kinking the chain on

the lower sprocket,

@Turn the crankshaft while holding the camshalt steady
such that the bolt holes align,

®Apply a non-permanent locking agent to both sprocket
bolts, and replace both bolts tightening them with 1.4
~ 1.6 kg-m (10~ 11.5 ft-lbs) of torque.

®lo verily that the valve timing will be correct, turn the
crankshaft to where the timing advancer “I” mark
aligns with the timing mark, and check that the
sprocket arrow which has the “T" adjoining it points
to the front of the engine (points parallel to the
cylinder head fitting surface),

l, Camshaft Sprocket 5. Chain lensioner
2, TDC Mark 6. Timing Mark

4. Camshaft Timing Mark = 7, Automatic Timing
1, Camshaft Chain Advancer

@Slip the chain off the sprocket, and then turn the
camshaft until the notch on the right end faces directly

ok

eRemove the stud nuts (8), and remove the cylinder
head holding plates.

@Remove the tachometer gear and the caps (2) from
the cylinder head cover (KZ400D).

®7urn the crankshaft such that the timing advancer “T”
mark aligns with the timing mark.

®Apply liquid gasket to the cylinder head cover O ring
fitting surface if necessary to hold the O ring to the
cylinder head cover, Check that all O rings (4) are
in place.

Liquid Gasket

@Place the cylinder head cover on the cylinder head,
and replace the nuts (8). Tighten them in the sequence
shown in Fig. 116, tightening cach nut first to 1.5
ke-m (11 ft-lbs) of torque and then to 2.5~ 3.0 kg-m
(18~ 22 ft-lbs).

Cylinder Head Cover Tightening Order (16)

®Replace the cylinder head cover caps.
®Apply a small amount of heat durable grease to the
tachometer gear, insert the gear, and reconnect the
cable to the cylinder head cover (KZ400D).

@Replace the tensioner assembly, The sequence is push
rod, spring, gasket, holder, push rod guide, and lock
nut, Tighten its screws, adjustit (Pg. 15 ), and replace
the cap and O ring,

DISASSEMBLY 35

@Apply liquid gasket if necessary to the breather cover
O ring groove Lo hole the O ring in place for installation,

eReplace the breather cover tightening its bolts (4) with
1.8~ 2.3 kg-m (13 ~ 16.5 ft-lbs) of torque. Each bolt
has a flat washer,

@Replace the breather cover bracket. Each bolt has a
lock washer,

@lnstall the fuel tank (Pg. 28).

@Replace the contact breaker cover and gasket.

CYLINDER HEAD

Removal:

#Remove the camshaft (Pg. 33).

®Remove the muffler collar nuts and lock washers, and
slide each muffler collar off its cylinder head studs,

e@Remove each rear foot peg to complete muffler removal.
Also, remove the muffler gasket from cach exhaust port,

®Remove the right and left side covers.

@Loosen the engine intake duct clamp for each carbu-
retor.

@Loosen the clamp that connects each air cleaner duct
to its carburetor, and slip it out of place.

reir leanenDuct Cla mp

Eng

@Slip the carburetors down and out of their ducts, pull
the carburetors free, and set them on top of the frame.

@Pull the leads off the spark plugs, and remove the spark
plugs.

@Disconnect the blue and the red/yellow ignition coil
leads,

wilgnition Coil Lead

| en

36 DISASSEMBLY

*®Remove the ignition coil bracket together with the
ignition ceil,

®RKemove the cylinder head bolts (4) using special 10
mm and 13 mm sockets and the cylinder head bolt
wrench handle (special tools),

A xe He raul Bolt. itwrestth ‘Socket ae
Me 57001371 77 ee a,

HG ndieyen | “

*

— »h

7

@Pull off the cylinder head, and remove the cylinder

head gasket. When the cylinder head is part of the
way Up, Insert a screwdriver between the cylinder head
and cylinder block through the camshaft chain, and
remove the screwdriver which is on top of the cylinder
head,

eFit the cylinder head on the cylinder block while at
the same time running the camshaft chain through the
cylinder head using 4 length of cord. Kemove the cord,
and use a screwdriver resting on the cylinder head to
keep the chain from falling.

ePlace a cylinder head holding plate (special tool) on
both sides of the cylinder head, and tighten both tn
place using the stud nuts (8),

tud Nuts (8)_

i

*Sel the sprockel on the camshalt near where it fits.
The arrowed side of the sprocket faces the right side
of the engine.

Installation:

@Replace the cylinder head gasket, using a new one if
it is deteriorated or damaged,

@Check to see that the oval O rings are in place in the
gasket,

®Run the camshalt through the camshaft chain from
the right side of the engine, and fit the chain on the
sprocket,

eUsing a 17 mm wrench on the crankshaft, turn the
engine to where the timing advancer “T" mark (the
line adjoining the “T”) aligns with the timing mark.

Next, turn the crankshaft counterclockwise exactly 90°
(44 turn). Verify crankshaft position by checking that
the timing mark Is aligned with the timing advancer
as shown in Fig. 126.

A .. Mark

eSlip the chain off the sprocket, and then turn the
camshaft until the notch on the right end faces directly
up.

®lurn the sprocket such that the arrow which has no

letter adjoining it points to the front of the engine
(points parallel to the cylinder head fitting surface),
slip the chain back on the sprocket, and fit the
sprocket up into place (the bolt holes will not be
aligned at this time).

DISASSEMBLY 37

NOTE: The camshaft chain must be fitted with the

crankshaft, sprocket, and camshaft positioned as just

described, Otherwise, the valve timing will be incorrect,

The reason for fitting the chain on the sprocket before

turning the crankshaft ts to avoid kinking the chain on

the lower sprocket.

@Jurn the crankshaft while holding the camshalt steady
such that the bolt holes align.

eApply a non-permanent locking agent to both sprocket
bolts, and replace both bolts tightening them with 1.4
~ 1.6 ke-m (10~ 11.5 ft-lbs) of torque.

®To verify that the valve timing will be correct, turn the
the crankshaft to where the timing advancer “T" mark
aligns with the timing mark, and check that the sprocket
arrow which has the “T" adjoining it points to the front
of the engine (points parallel to the cylinder head fit-
ting surface),

@Remove the stud nuts (8), and remove the cylinder
head holding plates.

®Remove the tachometer gear (KZ400D) and the caps
(2) from the cylinder head cover.

elurn the crankshaft such that the timing advancer “1
mark aligns with the timing mark.

38 DISASSEMBLY

#@Apply liquid gasket to the cylinder head cover O ring
fitting surface if necessary to hold the O ring to the
cylinder head cover, Check that all O rings (4) are
in place.

ePlace the cylinder head cover on the cylinder head,
and replace the nuts (8). Tighten them in the sequence
shown in Fig. 131, tightening cach nut first to 1.5
ke-m (11 ft-lbs) of torque and then to 2.5~3.0 kg-m
(18 ~ 22 fr-lbs),

Cylinder Head, Cylinder Head Cover Tightening Order

oy Pa =

mri

rats Hae Se
1 (Oqty We) _

@Replace the cylinder head bolts (4) using special 10
mm and 13 mm sockets (special tools), Tighten in
ihe sequence shown in Fig. 131, tightening the 6 mm
bolts with 2.5 ~ 3.0 kem (18 ~ 22 ft-lbs) of torque
and then the 6 mm bolls with |.1 ~ 1.3 kg-m (95
~ 113 in-lbs).

eReplace the cylinder head cover caps.
®Apply a small amount of heat durable grease to the
tachometer gear, insert the gear, and reconnect the
cable to the cylinder head cover.

@Replace the tensioner assembly, The sequence is push
rod, spring, gasket, holder, push rod guide, and lock
nut. Tighten its screws, adjust it (Pg, 15 ), and replace
the cap and O ring.

@lnstall the ignition coil bracket together with the ig-
nition coil,

@Connect the blue and the red/yellow ignition coil leads.

@Replace the spark plugs, and connect each spark plug
lead onto the plug.

eSlip the carburetors back into place the reverse of how
they were removed. Have the breather tube routed
between the air cleaner ducts. The throttle cables
go dlong the right side of the top tube,

@Qnce the ducts are all properly fitted on the carbu-
retors, tighten all four clamps.

@Route the carburetor tubes (4) to the rear through
their guide,

@Replace the right and left side covers.

e®For each muffler, fit the gasket and the end of the ©
muffler into its exhaust port, and attach the muffler
to the frame tightening its foot peg nut loosely. A
lock washer and flat washer go with the nut.

@Fit each split keeper and collar back into place, and
tighten the collar nuts evenly to avoid an exhaust leak,
There 15 a lock washer for each nut,

= a
m, Splitikeepersiaiy

*lighien the foot peg bolts securely,

#@Apply liquid gasket if necessary to the breather cover
O ring groove to hole the O ring in place for installation.

e@Replace the breather cover tightening its bolts (4) with
1.8~ 2.3 kp-m (13 ~ 16.5 ft-lbs) of torque. Each bolt
has a flat washer,

@Replace the breather cover bracket, Each bolt has a
lock washer,

elnstall the fuel tank (Pg. 28),

®Replace the contact breaker cover and gasket,

VALVES, VALVE GUIDES

Removal (per valve and valve guide):

#Remove the cylinder head (Pg. 35),

@Using the valve spring compressor assembly (special
tool) to press down the valve spring retainer (2), remove
the split keeper (1), =

DISASSEMBLY 39

*Being careful not to damage the oil seal, remove the
clip (5) and pull off the oil seal 6),

®Remove the tool, and then remove the Spring retainer,
outer spring 3), and inner spring (4.
*Push out the valve 7) or 72.

Valve and Valve Guides

I. Split Keeper
2. Spring Retainer
3. Outer Spring
4, Inner Spring

5. Clip

6, Oil Seal

7. Valve Guide

&. Washer

9, Washer

10, O Ring

ll, Exhaust Valve
12, Inlet Valve

40 DISASSEMBLY

@®Remove the washers & ‘9 (2)

eHeat the area around the guide to about 120~ 150°C
(250 ~ 300°F), and hammer lightly on the valve guide
arbor (special tool) to remove the guide out the top
of the head,

Installation (per valve and valve guide):

#Apply oil to the valve guide. Replace the O ring for
anew one if deterioted or damaged,

e@Heat the area around the valve guide hole to about
120~ 150°C (250~300°F), and drive the valve guide
in fram the top of the head using the valve guide arbor
(special tool),

@Ream the valve guide with the valve guide reamer
(special tool) even if the old guide is re-used.

eer 5 70015 =
01-162 =
@Lap the valve so that it will seat properly (Pg, 112).

@Replace the washers (2), push the oil seal into place
and replace its clip.

@Apply a thin coat of heat durable grease to the valve
stem, insert the valve, and replace the outer and inner
springs. The relatively concentrated portion of each
spring should face the cylinder head.

| Outer Spring eames |

—.

j
i

c og
QlonegSpring YA

a |

®Keplace the valve retainer, press it down with the valve
spring compressor assembly, and replace the split keeper.

#Remove the tool,

@lnstall the cylinder head (Pg. 36).

eCheck valve clearance (Pg. 14 ), and adjust if necessary.

CYLINDER BLOCK

Removal:

#Remove the cylinder head (Pg, 35),

@Remove the screwdriver, and pull off the cylinder
block,

Installation:

@Replace any of the cylinder block O rings, cylinder
base gasket, or oil passage O rings with a new one if
deteriorated or damaged.

y\ \
2) den Block) “Oy Ring

®Fit a piston base (special tool) into place at the crank-
case opening for each piston, and turn the crankshaft
with a 17 mm wrench such that each piston is situated
squarely on its piston base,

ee

istoniBae

@Compress the piston rings using a piston ring compres-
sor assembly (special tool) for each piston.

Pistonieang ere
vO 01-92

ePull out the camshaft chain, and let it hang over the
side of the crankcase.

@Fit the cylinder block on the crankcase studs, guide
the front camshaft chain guide inside the block, and
rest the bottom of the cylinders on the piston ring
compressors.

@Lift up the camshaft chain, use a screwdriver to keep
the chain from falling down into the cylinder block,

eWork the bottom of each cylinder past the rings, and
set the cylinder block in place while removing the
special Lools,

@install the cylinder head (Pg, 35).

DISASSEMBLY 41

PISTON, PISTON RINGS
Removal:

®Remove the cylinder block (Pg. 40),

eWrap clean cloth around the base of each piston to
secure iL in position for removal and so that no parts
will fall into the crankcase.

®Kemove one of the piston pin snap rings from each
piston.

®Remove cach piston by pushing its piston pin out the
side that the snap ring was removed, Use the piston
pin puller and adapter "B" (special tools) if necessary.

Piston Pin Puller,
57001-910 |

Adapter "Ba
57001-913))|

@eRemove the piston rings with the piston ring pliers
[special tool), To remove a ring by hand, spread the
ring opening with both thumbs, and then push up on
ihe opposite side.

Piston Ring Pliers
57001-115

42 DISASSEMBLY

Installation:

*Insiall the piston rings so that the correct side (marked
“N") faces up (Fig. 148). Don’t mix up the top and
second rings. The outer edges of the top ring are
oblique; the lower outer edge of the second ring is
notched, Insert the rings so that the gaps of the top
ring and the oil ring face the exhaust side and the gap
of the 2nd ring faces the inlet side,

(148)

Piston Rings

lop Ring

Second Ring

Oil Ring

®Apply a little oil to the piston pins, and replace the
piston and piston pins, The arrow on the top of each
Piston must point towards the front.

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@Fit a new piston pin snap ring into the side of each
piston,

®*Remove the cloth from under each piston,

@install the cylinder block (Pg. 40),

NOTE: If the piston is replaced with a new one, piston
to cylinder clearance changes (Pg. 115). Also, when a
new piston or piston pin is installed, check that the
piston to pin clearance is 0.006~ 0.013 mm,

To the Dealer: When possible, match parts from stock so
that a marked pin is assembled with an “A” piston and
an unmarked pin with an unmarked piston. Also, when
possible, use a “2" piston with a “2” cylinder bore and
an unnumbered piston with an unnumbered cylinder
bore,

DYNAMO FIELD COIL

Removal:

*Remove the right side cover, and disconnect the field
coil plug from its socket under the voltage regulator,

@Take out the shift pedal bolt, and remove the shift
pedal.

*#Remove the left foot peg bolt, left foot peg, and side
sland spring.

@Remove the engine sprocket cover screws (4), and pull
the cover free from the crankcase.

#Remove the dynamo and starter motor wiring guide.

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®Remove the starter motor cover and gasket.
@Remove the dynamo cover screws (8), and pull off
the dynamo cover,

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®Disconnect the oil pressure indicator switch lead and
the neutral indicator switch lead.

@Remove the starter motor chain guide and sprocket
guide (KZ400D).

®Remove the armature Allen bolts (3), and pull out the
armature.

DISASSEMBLY 43

@#Remove the field coil mounting Allen bolts (3), and
remove the field coil,

Installation:

@Set the field coil into place, and tighten its Allen bolts
(3). Use a non-permanent locking agent on each bolt,
and tighten the bolts to 0.7~0.8 kg-m (61~69 in-lbs),

#Fit the armature into place, and tighten its Allen bolts
(3). Use a non-permanent locking agent on each bolt,
and tighten the bolts to 0.7~0.8 kg-m (61~69 in-lbs),

@Fit the wiring into the dynamo cover grommets, and
push the grommets back into the cover,

®Apply a non-permanent locking agent to the screws,
and replace the starter motor chain guide and sprocket
guide (KZ400D). The sprocket guide bends out for
contact with the sprocket.

@#Connect the oil pressure indicator switch lead and
neutral indicator switch lead.

®Replace the dynamo cover, and tighten its screws (8).

@Replace the starter motor cover and gasket,

@Fit first the starter motor lead (KZ400D) and then the
dynamo wiring into the wiring guide, and screw the
guide back on the crankcase.

@Replace the engine sprocket cover using the shift shaft
oil seal guide (special tool) to protect the cover oil
seal, and tighten its screws, The wiring is routed in
front of the upper mounting bolt spacer.

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®Fit the side stand spring into place, and then secure
the left foot peg with its bolt,

@Replace the shift-pedal so that its end matches the
level of the dynamo cover lower rightscrew, and tighten
its bolt,

@Reconnect the plug to its socket under the voltage
regulator,

@®Replace the right side cover,

44 DISASSEMBLY

DYNAMO ARMATURE
Removal:

@Remove the right side cover, and disconnect the arma-
ture plug from its socket under the voltage regulator.

@lake out the shift pedal bolt, and remove the shift
pedal.

*Kemove the left foot peg bolt, left foot peg, and side
stand spring,

@Remove the engine sprocket cover screws (4), and pull
the cover free from the crankcase.

@®Remove the dynamo and starter motor wiring guide
(KZ400D).

®Remove the dynamo cover screws (8)
dynamo cover,

, and pull off the

@Remove the starter motor chain guide and sprocket
guide (KZ400D).

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Starter Motor Chain Guide ™.
\o FSB

Armature

@Remove the armature Allen bolts (3), and pull out the
armature,

Installation:

@Fit the armature into place, and tighten its Allen bolts.
Use a non-permanent locking agent on each bolt, and
tighten the bolts to 0.7 ~ 0.8 kg-m (61 ~ 69 in-lbs).

e@Fit the wiring into its dynamo cover grommets, and
press the grommets back into the cover.

®Apply a non-permanent locking agent to the screws,
and replace the starter motor chain guide and sprocket
guide (KZ400D). The sprocket guide bends out for
contact with the sprocket.

®Replace the dynamo cover, and tighten its screws (8).

®Fit first the starter motor lead (KZ400D) and then the
dynamo wiring into the wiring guide, and screw the
guide back on the crankcase.

*Replace the engine sprocket cover using the shift shaft
oil seal guide (special tool) to protect the cover oil seal,
and tighten its screws, The wiring is routed in front of
the upper mounting bolt spacer.

: J AGrpen Mounting

Bolt Space

@Fit the side stand spring into place, and then secure
the left foot peg with its bolt.

@Replace the shift pedal so that its end matches the level
of the dynamo cover lower right screw, and tighten its
balt.

#®Reconnect the plug to its socket under the voltage
regulator,

@Replace the right side cover,

STARTER MOTOR CLUTCH (Only on KZ400D),
DYNAMO ROTOR

Removal:

@fake out the shift pedal bolt, and remove the shift
pedal.

*Remove the left foot peg bolt, left foot peg, and side
stand spring,

#Remove the engine sprocket cover screws (4), and pull
the cover free from the crankcase,

Remove the dynamo cover screws (8), and pull off the
dynamo cover and gasket.

eit

®Hold the dynamo rotor steady with the dynamo rotor
holder (special tool), and remove the rotor bolt, The
bolt must be turned clockwise for removal.

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eUsing the special tool to hold the rotor steady, remove
the rotor and starter motor clutch assembly with the
dynamo rotor puller (special tool), There is a thrust
washer at the rear of the rotor,

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DISASSEMBLY 45

Installation:

@®Apply a small amount of heat durable prease Lo the
thrust washer, clean off any oil or dirt that may be
on the crankshaft taper or rotor hub, and replace it
lu the rear of the rotor. Place the assembly back on
the crankshaft.

®Apply a non-permanent locking agent to the rotor bolt
threads, and then tighten the bolt to 6.5~7.0 kg-m (47
~ 5] ft-lbs) of torque while holding the dynamo rotor
steady with the dynamo rotor holder (special tool).

®Replace the dynamo cover, gasket, and screws (8).

®Replace the engine sprocket cover using the shift shaft
oil seal guide (special tool) to protect the cover oil seal,
and tighten its screws.

#Fit the side stand spring into place, and then secure
the left foot peg with its bolt.

#Replace the shift pedal so that its end matches the level
of the dynamo cover lower right screw, and tighten its
bolt.

Disassembly:
#Remove the rollers, springs, and spring caps (3 ea) from
the starter motor clutch,

eWrap the rotor with cloth, and clamp it in a vise.

46 DISASSEMBLY

Remove the Allen bolts to separate the rotor and starter
motor clutch.

Starter Clutch

Assembly Note:

®Apply a non-permanent locking agent to the Allen
bolts, and tighten the bolts with 3.3 ~ 3.7 kg-m (24
~ 27 ft-lbs) of torque,

STARTER MOTOR CHAIN,
SPROCKETS (Only on KZ400D)
Removal:
@eKemove the dynamo rotor and starter motor clutch
(Pe. 45).
Pull off the starter motor chain and sprockets,

STARTER MOTOR (Only on KZ400D)

Removal:

@lfake out the shift pedal bolt, and remove the shift
pedal.

@#Remove the left foot peg bolt, left foot peg, and side
stand spring.

#Remove the engine sprocket cover screws (4), and pull
the cover free from the crankcase,

@Remove the dynamo cover screws (8), and pull off the
dynamo cover and gasket.

@Remove the starter motor cover and gasket.

eRemove the starter motor terminal nut and washer,

and remove the lead from the motor,

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eUsinga 10mm T wrench with a pivoted socket, remove
the starter motor retaining bolts (2).

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@Tap lightly on the starter motor body as shown in Fig.
173 to free the motor, and then pull it out,

CAUTION: Dot not tap on the starter motor shaft. Tap-
ping on the shaft may damage the motor.

Installation:
@Daub a little oil on the O ring.

®Place the starter motor back into position fitting the
shaft through the sprocket.

®Reconnect the motor lead onto the terminal. A lock
washer goes with the nut,

*Apply a non-permanent locking agent to the starter
motor retaining bolts, and tighten the bolts, Each
bolt has a flat washer.

@®Replace the starter motor cover and gasket,
@eReplace the dynamo cover, gasket, and screws (8),
®Replace the engine sprocket cover using the shift shaft
oil seal guide (special tool) to protect the cover oil seal,
and tighten its screws,

fOilSeallGuide

Starter Motor

1. Circlip 9, Shaft I7. Armature

2. Shims 10, Gears 18. Shims

3, O Ring 11, Gasket 19, Brush Plate

4. End Cover 12, End Plate 20, Brush Lead

5. Screws 13, Gasket 21. Carbon Brushes
6, Lock Washers 14. Yoke Assembly 92. O Ring

7. Shims 15, Field'‘Coil Lead 93. End Cover

§. Grease Seal lo, Shims

DISASSEMBLY 47

®Fit the side stand spring into place, and then secure
the left foot peg with its bolt.

@Replace the shift pedal so that its end matches the level
of the dynamo cover lower right screw, and tighten its
bolt.

Disassembly:

®Remove the starter motor shaft circlip (1) and shims ‘2°.

@®Remove the screws 5) (2) , and remove the end covers
4) 29 (2), shaft), and gears ‘i (2). The grease seal
8 and Oring 3) may be removed with a hook,

@Remove the end plate 12, gaskets 11) 12, and armature
I?) from the shaft side.

@Remove the screw which connects the brush lead 20
to the field coil lead 1%), and remove the brush plate 13.
Ihe screw has a lock washer. These is an O ring
2? at the brush side of the housing.

NOTE: The yoke assembly 14 is not meant to be

disassembled.

Assembly Notes:

1. Replace the grease seal with a new one if it was re-
moved, and replace any O rings that are deteriorated
or damaged with new ones,

48 DISASSEMLY

2, Align the notch on the end plate with the nub on
the housing, and align the line on each end cover
with its line on the housing.

IGNITION COIL ~

Removal:

eRemove the fuel tank (Pe. 28).

@Pull off the lead from each spark plug,

@Disconnect the blue and the red/yellow ignition coil
leads.

@Remove the bolts (2) that connect the ignition coil
to the frame, and remove the ignition coil,

Installation Note:
@Use only the Kawasaki ignition coil bolts to mount

the ignition coil, Bolts of a different composition
may adversely affect ignition coil performance.

CONTACT BREAKER

Removal:

eRemove the contact breaker cover and gasket.

@Remove the contact breaker base screw. The screw
has a flat and a lock washer.

@®Loosen the contact breaker nut, and remove the two
leads,

Installation Notes:

l. The sequence on the contact breaker bolt is bolt
head, contact breaker lead, spring, large insulator,
small insulator (in contact breaker hole), large in-
sulator, condenser lead, flat washer, lock washer,
and nut,

2, After installation, adjust the ignition timing (Pg.
12).

CONDENSER

Removal:

eRemove the contact breaker cover and gasket,
eRemove the condenser screw. The screw has a lock
washer,

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@Loosen the contact breaker nut, and remove the con-

denser lead to complete condenser removal.
Installation Note:

@]he sequence on the contact breaker boltis bolt head,
contact breaker lead, spring, large insulator, small insu-
lator (in contact breaker hole), large insulator, con-
denser lead, flat washer, lock washer, and nut,

TIMING ADVANCER
Removal:

#Kemove the contact breaker cover and gasket.

@Take out the contact breaker plate screws (3), and re-
move the plate,

eWith one wrench on the crankshaft rotation nut to
Keep the shaft from turning, remove the bolt, and take
off the timing advancer.

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Installation:

efit the timing advancer onto the crankshaft matching
ts notch with the pin in the end of the crankshaft,

and replace the crankshaft rotation nut and the bolt,

lighten the bolt with 2,.3~ 2,7 kg-m (16.5~ 19.5 ft-lbs)
ol Lorque,

®Replace the contact breaker plate, and tighten its
screws loosely,
eAdjust the ignition timing (Pe. 12).

Disassembly :
ePull off the cam.

DISASSEMBLY 49

@*Remove the two C rings, washers, and weights,
@Remove the thrust washer from cach weight shaft.

Assembly Note:

eWhen installing the cam, align the mark on the cam
with the notch on the advancer body.

CLUTCH, PRIMARY CHAIN

Removal:

eWith the motorcycle on its center stand, place an oil
pan beneath the engine, and remove the engine oil
drain plug and oil filter to drain out the ail,

eUndo the right foot peg bolt, and remove the foot peg.

*Mark the position of the kickstarter pedal so that it
can later be replaced on the kick shaft in the same
position,

®lake out the kickstarter pedal bolt, and remove the
kickslarter pedal.

@®Remove the contact breaker cover and gasket.
®Kemove the contact breaker plate screws (3), and
remove the plate.

®Kemove the timing advancer bolt, and pull off the
liming advancer.

@Remove the screws (12), and pull off the engine cover
and gasket,

@Remove the clutch spring bolts (5), washers 1@, and
springs “3 (4 ea).

@Pull off the spring plate 12, pull out the spring plate
pusher i), and tilt the motorcycle so that the steel
ball (a will Fall out,

50 DISASSEMBLY

Clutch Construction

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}

. Friction Plate

9, Steel Plate

. Steel Ball

. Spring Plate Pusher
. Spring Plate
Spring

Primary Sprocket Washer

2, Circlip 15. Bolt
. Primary Chain 16. Shim
4. Clutch Housing \7. Circlip
. Thrust Washer 18. Oil Pump Drive Gear
. Clutch Hub 19. Circlip
. Steel Ring 20, Pin

#lo remove the oil pump drive gear 18 and pin 20 ,
remove the circlip 19, pull off the gear, and pull out
the pin.

®Remove the clutch hub circlip 17) and shim(s) 4.

@#Remove the friction plates (8) (6), steel plates (9) (5),
steel rings (7) (6), and clutch hub (6. There is a
thrust washer (5) al the rear of the clutch hub. Installation:

eRemove the primary sprocket circlip 2) . elf the oi] pump drive gear was removed, replace its pin,

ePull off the clutch housing (@), primary sprocket (1), fit on the gear, and replace the circlip, The protruding
and primary chain (3) together, side of the hub faces the housing.

Protruding Side

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/ Oil PumpjDrivexGear

nil

@Fit the primary chain on the clutch housing and primary
sprocket, and fit the assembly into place. The pro-
truding side of the primary sprocket faces out. Turn
the oi] pump gear by hand if necessary so that it
meshes with the oil pump drive gear.

eReplace the primary sprocket circlip.

@eReplace the thrust washer (thick) and the clutch hub,

@Replace the shim(s) and clutch hub circlip. The shim/(s)
should take up all the play between the hub and
circlip. If not, add more shim(s).

@Replace the friction plates (6), steel rings (6), and steel
plates (5). The sequence is friction plate, steel ring,
steel plate, friction plate finishing with a steel ring.

@insert the steel ball and spring plate pusher,

@Replace the spring plate aligning the raised points on
the plate with the punch marks on the hub,

*@Replace the spring bolts (4), each with its washer and
spring. Tighten them with 0.9~1.1 kgm (78~113
in-Ibs) of torque in a cross pattern by hand rather than
use compressed air, which might make spring pressure
uneven,

DISASSEMBLY 51

eCheck that the wire band in the engine cover crank-
shaft oil seal has not slipped out of its proper position.

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eUsing a new engine cover gasket, fit the engine cover
onto the crankcase. Use the kick shaft oil seal guide
(special tool) to protect the kick shaft oil seal. Tighten

the screws (12) firmly. Be sure to include the contact
breaker lead clamp with its engine cover screw,

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§57001: 265

ma Kick Shaft.Oil Seal Guide 4

@f-jt the timing advancer onto the crankshaft matching
its notch with the pin on the end of the crankshaft,
and tighten its bolt with 2.3 ~ 2.7 kge-m (16.5~ 19.5
ft-lbs).of torque,

@Replace the contact breaker plate, and tighten its screws
(3) loosely.

@Replace the kickstarter pedal back on the kick shaft in
its original position, and tighten its bolt,

@Replace the right foot peg. A lock washer goes with
the bolt,

e@Make sure the O rings are in place, and replace the oil
filter and drain plug. Tighten the oil filter with [1.5 ~
2.0 kg-m (11 ~ 14.5 ft-lbs) of torque and the drain
plug with 2.7 ~3.3 kg-m (19.5 ~24 ft-lbs).

Drain Plug

RS / «0° Rings

Protruding Side

—_ ae
/ Oil PumpjDrivexGear

nil

@Fit the primary chain on the clutch housing and primary
sprocket, and fit the assembly into place. The pro-
truding side of the primary sprocket faces out. Turn
the oi] pump gear by hand if necessary so that it
meshes with the oil pump drive gear.

eReplace the primary sprocket circlip.

@eReplace the thrust washer (thick) and the clutch hub,

@Replace the shim(s) and clutch hub circlip. The shim/(s)
should take up all the play between the hub and
circlip. If not, add more shim(s).

@Replace the friction plates (6), steel rings (6), and steel
plates (5). The sequence is friction plate, steel ring,
steel plate, friction plate finishing with a steel ring.

@insert the steel ball and spring plate pusher,

@Replace the spring plate aligning the raised points on
the plate with the punch marks on the hub,

*@Replace the spring bolts (4), each with its washer and
spring. Tighten them with 0.9~1.1 kgm (78~113
in-Ibs) of torque in a cross pattern by hand rather than
use compressed air, which might make spring pressure
uneven,

DISASSEMBLY 51

eCheck that the wire band in the engine cover crank-
shaft oil seal has not slipped out of its proper position.

@

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Engine ¢ over {crantehartoil: is

lz Se x = “a = —,

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\h 5 ic. ;

eUsing a new engine cover gasket, fit the engine cover
onto the crankcase. Use the kick shaft oil seal guide
(special tool) to protect the kick shaft oil seal. Tighten

the screws (12) firmly. Be sure to include the contact
breaker lead clamp with its engine cover screw,

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§57001: 265

ma Kick Shaft.Oil Seal Guide 4

@f-jt the timing advancer onto the crankshaft matching
its notch with the pin on the end of the crankshaft,
and tighten its bolt with 2.3 ~ 2.7 kge-m (16.5~ 19.5
ft-lbs).of torque,

@Replace the contact breaker plate, and tighten its screws
(3) loosely.

@Replace the kickstarter pedal back on the kick shaft in
its original position, and tighten its bolt,

@Replace the right foot peg. A lock washer goes with
the bolt,

e@Make sure the O rings are in place, and replace the oil
filter and drain plug. Tighten the oil filter with [1.5 ~
2.0 kg-m (11 ~ 14.5 ft-lbs) of torque and the drain
plug with 2.7 ~3.3 kg-m (19.5 ~24 ft-lbs).

Drain Plug

RS / «0° Rings

52 DISASSEMBLY

eFill the engine with oil, check the level (Pg.181),
and add more if necessary.
eAdjust the ignition timing (Pg. 12).

CLUTCH RELEASE
Removal:

@fake out the shift pedal bolt, and remove the shift
pedal,

@Remove the left foot peg bolt, left foot peg, and side
stand spring.

®Remove the engine sprocket cover screws (4), and pull
the cover free from the crankcase.

@Remove the cotter pin from the clutch release lever,
and free the clutch inner cable tip from the lever and
engine sprocket cover,

Clutch Inner Cable Tip”

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@®Remove the chain guard screws (4) to remove the chain
guard,

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Pakciuich Rele

@Remove the clutch release outer gear screws (2), and
separate the two gears.

Installation:

eFit the worm gears together so that, as they begin to

mesh, the punch mark on the inner gear aligns with
the raised point on the outer gear,

()

Raised Point

efit the clutch release gears back into the engine
sprockel cover, apply a non-permanent locking agent
to the screws, and then tighten the screws, When
the gears are fully meshed, their position should be
as shown in Fig. 198.

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®Apply a non-permanent locking agent to the chain
guard screws, and replace the chain guard,

®Run the clutch cable into the engine sprocket cover
and spring, and fit the tip of the inner cable into the
clutch release lever,

eUsing a new cotter pin, secure the cable tip to the
release lever,

®Replace the engine sprocket cover using the shift shaft
oil seal guide (special tool) to protect the oil seal in
the cover, and tighten its screws.

=

@Fit the side stand spring into place, and then secure
the left foot peg with its bolt,

@Replace the shift pedal so that its end matches the
level of the dynamo cover lower right screw.

ENGINE SPROCKET

Removal:

eCheck that the transmission is in neutral,

@lake out the shift pedal bolt, and remove the shift
pedal,

eRemove the left foot peg bolt, left foot peg, and side
stand spring.

eRemove the engine sprocket cover screws (4), and pull
the cover free from the crankcase.

eRemove the clip carefully from the drive chain master
link with pliers, remove the master link, and remove
the drive chain from the engine sprocket.

@*Straighten the side of the splined washer that is bent
over the side of the engine sprocket nut.

@Hold the engine sprocket steady using the engine
sprocket holder (special tool), and remove the engine
sprocket nut.

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@Pull off the splined washer and the engine sprocket.

Installation:

®Replace the engine sprocket and splined washer, and
then tighten the engine sprocket nut with 12~15 kg-m
(87 ~ 108 ft-lbs) of torque while using the engine
sprocket holder to keep the sprocket steady.

®Bend back one side of the splined washer over the side
of the nut.

@fFit the drive chain back on the sprockets with the ends
on the rear sprocket as shown in Fig. 202.

DISASSEMBLY 53

————

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: 4

@Replace the chain master link with pliers, The direction
of the master link clip should be as shown in Fig, 203,

Chain MasteqLink Clip
Se

eReplace the engine sprocket cover using the shift shalt
oil seal guide (special tool) to protect the oi! seal in the
cover, and tighten its screws.

@fFit the side stand spring into place, and then secure the
left foot peg with its bolt.

@Replace the shift pedal so that its end matches the level!
of the dynamo cover lower right screw.

NEUTRAL INDICATOR SWITCH

Removal:

@lake out the shift pedal bolt, and remove the shift
pedal,

@Remove the left foot peg bolt, left foot peg, and side
stand spring.

@Remove the engine sprocket cover screws (4), and pull
the cover free from the crankcase.

94 DISASSEMBLY

@Kemove the dynamo and starter motor wiring guide.

®Pull off the neutral indicator switch lead from the
switch,
eRemove the neutral indicator switch and gasket.

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Installation:

*®Apply a non-permanent locking agent to the threaded
portion, and replace the neutral indicator switch and
gasket tightening it with 1.5~ 2.0 kg-m (11 ~ 14.5
ft-lbs) of torque.

eit the lead back on the switch,

@rit first the starter motor lead and then the dynamo
wiring Into the wiring guide, and screw the guide back
on the crankcase.

®Replace the engine sprocket cover using the shift shaft
oil seal guide (special tool) to protect the oil seal, and
lighten its screws,

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efit the side stand spring into place, and then secure the
left foot peg with its bolt.

®Replace the shift pedal so that its end matches the level
of the dynamo cover lower right screw,

ENGINE OIL PUMP
Removal:

@Remove the clutch and primary chain (Pg, 49).
@Remove the oil pump screws (4), and pull off the oil
pump. There are three O rings in the crankcase.

Installation Note:
@Replace any O rings that are deteriorated or damaged.

Disassembly:

@Remove the C ring 1)and washer 2).

Separate the oil pump halves 3 (7) , and remove the
rotors (40.5

®Kemove the pin (8), and separate the gear (9) and oil
pump half (7).

Assembly Note:
eCheck whether or not the rotors rotate smoothly.

EXTERNAL SHIFT MECHANISM

Removal:

@Remove the clutch and primary chain (Pg. 49).

@lake out the shift pedal bolt@, and remove the shift
pedal(1).

@®Remove the left foot peg bolt, left foot peg, and side
stand spring,

@#Remove the engine sprocket cover screws (4), and pull
the cover free from the crankcase.

@Kemove the external shift mechanism stopper 9 ,

®Move the external shift mechanism pawl 1) out of its
position on the end of the shift drum, and pull out
the external shift mechanism (7).

http://www.kz400.com/ DISASSEMBLY 55

Engine Oil Pump

|. C Ring ‘+, Inner Rotor 7. Oil Pump Half
2. Washer 5. Outer Rotor 8. Pin
3. Oil Pump Half 6. Nock Pin 9, Oil Pump Gear

Shift Mechanism

|. Shift Pedal

2, Pedal Rubber

3, Shift Pedal Bolt
4, Lock Nut

5. Return Spring Pin
6, Return Spring

7, Shift Shaft

5. Spring

9, Shift Mechanism Stopper
10, Screw

Li. Shift Mechanism Pawl

56 DISASSEMBLY

Installation:

@/nsert the shift shaft oil seal guide (special tool) in the
crankcase shift shaft oil seal, run the external shift
mechanism through the crankcase, and place its arm on
the shift drum pins.

efShifyShafuOil'Seal Guide
SPS 7.001264
3 ih

—

@Apply non-permanent locking agent to the screws, and
replace the external shift mechanism stopper,

@Replace the engine sprocket cover using the shift shaft
oil seal guide (special tool) to protect the oil seal in the
cover and tighten its screws,

a |

ot
os

_ Engine Spr

elit the side stand spring into place, and then secure the
left foot peg with its bolt,

@Replace the shift pedal so that its end matches the level
of the dynamo cover lower right screw, and tighten its
bolt.

e@|nstall the clutch and primary chain (Pg, 50),

TRANSMISSION

Removal:

@Remove the engine (Pg. 23).

@Set the engine on a clean surface or, preferably, into a
disassembly apparatus with some means of holding the
engine steady while parts are being removed,

@Remove the starter motor cover and gasket.

* @Remove the dynamo and starter motor wiring guide.

http://www.kz400.com/

— # ae

a

Jl =. ot : : : > LA
WAlbynamo & Starter

WWitina Guide

®Pull the neutral indicator switch lead from the switch.

eDisconnect the oil pressure indicator switch lead, and
push it through‘the starter motor lead hole to free it
from the crankcase.

@Remove the dynamo cover screws (8)
dynamo cover and gasket,

®Hold the dynamo rotor steady with the dynamo rotor
holder (special tool), and remove the rotor bolt. The
bolt must be turned clock wise for removal,

, and pull off the

@Using the special tool to hold the rotor steady, remove
the rotor and starter clutch assembly with the dynamo
rotor puller (special tool). There is a thrust washer at
the rear of the rotor,

http://www.kz400.com/

=. —) = a

ees BO YnomOMBoro Holder

007925

ePull off the starter motor sprocktes and chain (KZ400D),
®Kemove the starter motor retaining bolts (2) (KZ400D).
®lap lightly on the starter motor body as shown in

Fig. 217, and pull out the starter motor (KZ400D).

| tn

: Biartor Motor

my =: ST —F
%

a, +

CAUTION: Do not tap on the starter motor shaft,
Tapping on the shaft may damage the motor (KZ400D).
@Remove the contact breaker cover and gasket.

@Take out the contact breaker plate screws (3), and
remove the plate,

eWith one wrench on the crankshaft rotation nut to
keep the shaft from turning, remove the bolt, and take
off the timing advancer,

DISASSEMBLY 57

@Pull off the spring plate and spring plate pusher,
@Push in on the push rod to remove the steel ball,

_. Steel[Ball Y,
sa”

@Remove the clutch hub circlip and shim(s).

®Remove the friction plates (6), steel rings (6), stee!
plates (5), and clutch hub. There is a thrust washer at
the rear of the clutch hub.

@Remove the primary sprocket circlip.

a)

e@Pull off the clutch housing, primary sprocket, and
primary chain together,
®Remove the external shift mechanism stopper.

eMark the position of the kickstarter pedal so that it can
later be replaced on the shaft in the same position,
@Remove the kickstarter pedal bolt, and remove the
kickstarter pedal,

@Remove the screws (12), and pull off the engine cover
and gasket,

@Remove the clutch bolts, washers, and springs (4 ea).

@®Move the external shift mechanism pawl out of its
position on the end of the shift drum, and pull out the
external shift mechanism,

@®Remove the upper crankcase half bolts (6) and carbu-
retor tube guide,

@®]urn the engine upside down, and remove the lower «
crankcase half bolts (14).

http://www.kz400.com/

58 DISASSEMBLY

@Lift off the lower crankcase half,
@Remove the oil passage O ring.

@]ake out the drive shaft and output shaft assemblies,
@Kemove the shift drum stopper.

eRemove the shift drum positioning bolt, O ring, spring,
and pin.

@®Remove the drive shalt 3rd gear shift fork cotter pin,
and pull out the shilt fork guide pin,

eRemove the operating plate circlip.

ePull out the shift drum, and remove the operating
plate and drive shaft 3rd gear shilt fork,

@Remove the circlip, pull out the shift rod, and remove
the two remaining shift forks.

Installation:

®Remove the sump plate, clean out the lower crankcase
hall thoroughly, and then replace the sump plate. Use
ad non-permanent locking agent on the sump plate
screws,

®|nsert the shift rod running it through the output shaft
4th gear shift fork and then through the output shaft
5th gear shift fork. The output shaft 4th gear shift
fork guide pin is more centrally located than on the
other shift fork. Install the circlip in the groove on
the shift rod.

-

.

| Output Shaft4th Gear:

Shift Fork. J |

Output Shaf

"Shift Fork.

@lnsert the shift drum into the crankcase part way, and
fit the drive shaft 3rd gear shift fork on the drum with
the part which houses the pin facing the crankshaft.

yes i “4
a

— aye 3 a st ‘all ‘
[Gear Shift Fork

@®Check to see that the operating plate pin is in place,
fit the operating plate onto the end of the shift drum
with the nub facing out, and replace the circlip.

\. ° > _
\JNub

'
« >

@Insert the shift fork guide pin and cotter pin and bend
back the ends of the cotter pin,

@Push the shift drum in the rest of the way, and have
each shift fork guide pin riding in its drum groove.

eCheck that the drive shaft and output shaft set rings
and the oil passage nozzle are in place, and daub a
little engine oil on the set rings, blow the oil passage
nozzle clean with compressed air.

http://www.kz400.com/

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OutputiShaftiserds) ng ieacge Mme DrivelshaftiserRing

_ = \ ) ae en so |

Zz “Oil Passage)Noz ‘le
= SS

®Fit the output shaft and drive shaft assemblies fully
into place,

@Replace the shift drum stopper, and punch the screws
aller tightening its screws.

eKeplace the shift drum positioning pin, spring, O ring,
and bolt.

eCheck that the drive shaft assembly, output shaft
assembly, and shift drum all turn easily,

®Replace the oil passage O ring,

*Check to see that the following parts are in place: oil
Pressure relief valve, output shaft oil cup, crankshaft
bushing halves (2), push rod oil seal, crankshaft oil seal
(wire band side facing in). Apply a litthe engine oil to
all bushings.

Lower Crankcase Half

Upper Crankcase Half

iq
=m '

eClean of f and wipe dry the fitting surfaces of the crank-
case halves, and apply liquid gasket to the fitting surface
of the upper crankcase half.

e@Fit the lower crankcase half on the upper crankcase
half, and replace the lower crankcase half bolts (14).

DISASSEMBLY 59

Tighten first the 8 mm bolts (4) in the sequence shown
in Fig 231, tightening first cach bolt to 1.5 ke-m
(11 ft-lbs) of torque and then 2.5 ~ 3,0 kg-m (18 ~ 22
ft-lbs). Next, tighten the 6 mm bolts all lightly and
then with 0.8~1.0 ke-m (69~87 in-Ibs).

@lurn the engine right side up, and then tighten the
upper crankcase half bolts (6) with O.8~ 1.0 kg-m (69
~ 87 in-lbs) of torque. Include the carburetor tube
guide with its bolt.

@lnsert the shift shaft oil seal guide (special tool) in the
crankease shift shaft oil seal, run the external shift
mechanism shaft through the crankcase, and place its
arm on the shift drum pins.

Crankcase Bolts Tightening Order @3i)

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1 1]
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-

60 DISASSEMBLY

®Apply a non-permanent locking agent to the screws,
replace the external shift mechanism stopper, and
lighten the screws,

efit the primary chain on the clutch housing and
primary sprocket, and fit the assembly into place.
The protruding side of the primary sprocket faces
out, Turn the oil pump gear by hand if necessary
so that it meshes with the oil pump drive gear.

-.
—

= Oil'Pump Geary

- ‘=

@Replace the primary sprocket circlip.

®Replace the thrust washer (thick) and the clutch hub,

@Replace the shim(s) and clutch hub circlip. The shim(s)
should take up all the play between the hub and circlip.
If not, add more shim/(s).

@Replace the friction plates (6), steel rings (6) and steel
plates (5). The sequence is friction plate, steel ring,
steel plate, friction plate finishing with a steel ring.

®lnsert the ball bearing and spring plate pusher,

®Replace the spring plate aligning the raised points on
the plate with the punch marks on the hub,

*@Replace the spring bolts (4), each with its washer and
spring. Tighten them with 0.9~1.1 kg-m (78~113
in-lbs) of torque in a cross pattern by hand rather than
use compressed air, which might make spring pressure
uneven.
shaft oil seal has not slipped out of its proper position.

eUsing a new engine cover gasket, fit the engine cover
onto the crankcase. Use the kick shaft oil seal guide
(special tool) to protect the kick shaft oil seal. Tighten
the engine cover screws (12) firmly. Be sure to include
the contact breaker lead clamp with its engine cover
screw,

http://Awww.kz400.com/

~57001-265

eFit the timing advancer onto the crankshaft matching
its notch with the pin on the end of the crankshaft,
and tighten its bolt with 2.3 ~ 2.7 kg-m (16.5 ~ 19.5
ft-lbs) of torque.

®Replace the contact breaker plate, and tighten its
screws (3) loosely,

eReplace the contact breaker cover and gasket,

@Place the kickstarter pedal into its original position,
and tighten its bolt.

@®Run the starter motor lead through its crankcase hole,
daub a little oil on the starter motor O ring, and place
the starter motor back into position (KZ400D),

®Apply a non-permanent locking agent to the starter
motor retaining bolts, and then tighten the bolts. Each
bolt has a flat washer (KZ400D).

efit the starter motor chain on its sprockets, and push
the sprockets back into place (KZ400D).

@Apply a small amount of heat durable grease to the
ihrust washer, clean off any oi] or dirt thal may be
on the crankshaft taper or toror hub, and replace it
to the rear of the rotor. Place the assembly back on
the crankshaft.

@Apply a non-permanent locking agent to the rotor bolt
threads, and then tighten the bolt to 6.5~7.0 kg-m (47
~ 51 ft-lbs) of torque while holding the dynamo rotor
steady with the dynamo rotor holder (special tool),

@Replace the dynamo cover, gasket, and screws (8).

@Run the oil pressure indicator switch lead through the
starter motor lead hole, and connect it to the switch
lead,

eConnect the neutral indicator switch lead to the switch.

@Fit first the starter motor lead and then the dynamo
wiring into the wiring guide, and screw the guide back
on the crankcase.

e@Replace the starter motor cover and gasket.

elnstall the engine (Pg. 25),

eAdjust the ignition timing (Pg. | 2).

Shift Drum Disassembly:

@Drop out the operating plate pin 29).

@Remove the shift drum pin plate 36 .
a lock washer (37) .

@Pull out the pins 5) (6).

@To remove the shift drum needle bearing 36, use a
hook or some other tool to pull it out of the crankcase
wall. Removal necessitates replacement for a new one.

The screw has

http://www.kz400.com/

DISASSEMBLY 61

Shift Drum, Drive Shaft, Output Shaft

28. Operating Plate 52. Output Shaft
9, Needle Bearing 929. Operating Plate Pin 53. 2nd Gear (O)
10, Shim 30, Drum Positioning Bolt 54. Spline Washer
ll. Shim (Bronze) 31.0 Ring 55. Circlip
12, Shim =i Spring 56. 5th Gear
13, 2nd Gear (D) 33. Pin 57. Circlip
| 14. 5th Gear (D) 34. Shift Drum 58. Spline Washer
. 15. Copper Bushing 35. Pins 59. 3rd Gear (O)
NR 16. Spline Washer 36, Drum Pin Plate 60. Spline Washer
|. Oil Seal 17. Circlip 37. Lock Washer 61. Circlip
2, Clutch Push Rod 18. 3rd Gear (D) 38. Screw 62. 4th Gear (O)
3, Shift Rod 19, Circlip 39. Shift Drum Stopper 63. Ist Gear (O)
4, Sth Gear Shift Fork 20, Spline Washer AQ. Screw 64. Shim
5. 4th Gear Shift Fork 21. 4th Gear (D) 41. Cotter Pin 65. Shim
6, Circlip 22, Drive Shaft 42, Guide Pin 66. Needle Bearing
7. Bush 23. Set Ring 43. 3rd Gear Shift Fork 67, Needle Bearing Bushing
8, Needle Bearing Bushing 24, Ball Bearing 44, Engine Sprocket Nut 68. Circlip

. Splined Washer

. Engine Sprocket

. Output Shaft Collar
. ORing

. Drive Shaft Bushing 19. Oil Seal
26. Shift Drum Needle Bearing 50. Set Ring
27. Circlip 31. Ball Bearing

62 DISASSEMBLY

Shift Drum Assembly Notes:
1. To install a new shift drum needle bearing, use the
shift drum bearing driver (special tool) to drive it in,

pS fee. Shift Drum Needle Bearing

> 5
Ls = \
4,
i

2, Be sure that the screw is firmly tightened.

Drive Shaft Disassembly:
@Pull out the clutch push rod (2) with its oil seal 4),
@Pull off the needle bearing bushing ().

Remove the circlip (6), and pull off the needle bearing

9) and shim(s) do and? .

ePull off 2nd gear 4}, 5th gear 7, copper bushing 45),
and spline washer ‘é) .

@Remove the circlip (7), and pull off 3rd gear i .

@Remove the circlip 79 , and pull off the spline washer
(20) and 4th gear (21)

®Pull off the drive shaft bushing @% and ball bearing
24 Logether using the stem bearing puller and adapter
(special tools).

“oy

Stem Bearing Adapter
57001-1466 ©

Drive Shaft Assembly Notes:

1. Replace the drive shaft ball bearing and bushing
using the transmission circlip driver (special tool),

_ Transmission Circlip Driver™

c 007:

http://www.kz400.com/

2, Be sure that all parts are put back in the correct
sequence and all circlips are properly in place (replace
any that are bent or damaged). Proper sequence from
Ist gear is Ist gear, 4th gear, spline washer, circlip,
3rd gear, circlip, spline washer, copper bushing, 5th
gear, 2nd gear, shim(s), needle bearing, circlip, and
needle bearing bushing. The shim(s) should take up
all the play. If not, add more shim (s).

3, Ist gear—part of drive shaft
4th gear—dogged, dogs face 3rd gear
3rd gear—double dogged, tooth side dogs face 4th

gear, 22 teeth
Sth gear—dog recesses, dog recess side faces 3rd gear
2nd gear—no dogs, no dog recesses

4, Use the transmission circlip driver (special tool) to

replace the two inner circlips without damage. To
use the tool, fit the inner part on the shaft with
the end at the circlip groove, set the circlip on the
end of the inner part, place the driver against the
circlip, and use a hammer to tap the circlip into place.

Transmission Circlip|Driver
\\ 570015380

5. Fit the copper bushing and 3rd gear with their oil
holes matching the oi! holes in the shaft,

6. Apply a thin coat of heat durable grease to the push

rod before insertion.

Output Shaft Disassembly:

Pull off the needle bearing bushing 7.

@Remove the circlip 6@, and pull off the needle bearing
66) and shim(s) €@ 65) .

Pull off Ist gear 6) and 4th gear @2 .

@Remove the circlip 6! , and pull off the spline washer
60), 3rd gear 69), and spline washer 58),

@Remove the circlip 37), and pull off Sth gear 56 .

@Remove the circlip «5, and pull off the spline washer
84) and 2nd gear (53.

®Straighten the side of the splined washer 45 that is bent
over the side of the engine sprocket nut 44.

®@Hold the engine sprocket steady using the engine
sprocket holder (special tool), and remove the engine
sprocket nut.

http://www.kz400.com/

Engine Sprocket Holder

@Pull off the splined washer and the engine sprocket (46).
®Slide off the oil seal 49 .

ePull off the output shaft collar 47 and O ring @@.

@To remove the output shaft ball bearing si), first
fit the stem bearing puller (special tool) into place
upside down, and tighten to create a space between
the bearing and flange. Next, fit the puller on right
side up, and pull off the bearing.

_ Flange 242)

*
i

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y
,

Stem Bearing Puller
57001-158 —

Output Shaft Assembly Notes:

|. Replace the output shaft ball bearing using the
transmission circlip driver (special tool).

2. Replace the O ring if damaged.

3. Be sure that all parts are put back in the correct
sequence and all circlips are properly in place (replace
any that are bent or damaged). Proper sequence from
the engine sprocket side is 2nd gear, spline washer,
circlip, 5th gear, circlip, spline washer, 3rd gear, spline
washer, circlip, 4th gear, Ist gear, shim(s), needle
bearing, circlip, and needle bearing bushing. The

DISASSEMBLY 63

shim(s) should take up all the play. If not, add

more shim(s).

2nd gear—dog holes, side which is sunk further in

faces 5th gear

5th gear—double dogged, tooth side dogs face 2nd

gear

3rd gear—dog recesses, recess side faces 5th gear

4th gear—single dogged, dog side faces Ist gear

Ist gear—dog holes, side which Is sunk further in faces

4th gear

5. Use the transmission circlip driver (special tool) to
replace the three inner circlips without damage.

6. Be sure that the ball bearing oil seal wire band side
faces In.

7. Tighten the engine sprocket nut to 12 ~ 15 kg-m
(87 ~ 108 ft-lbs) of torque, using the engine sprocket
holder to keep the sprocket steady. Be sure to bend
back one side of the splined washer over the side of
the nut.

KICKSTARTER

Removal:

eSplit the crankcase as explained in transmission removal
(Pg. 56). The transmission itself does not require
removal.

eStraighten out the washer (2 ends which are bent over
the side of the ratchet gear arm stopper bolts 1, and
remove the stopper 3.

eRemove the circlip 25 which holds the spring guide
14 jn place.

ePull off the spring guide.

®Remove the kick spring 12.

@Remove the circlip 12 which is against the kick shaft
collar (1).

@Remove the kick shaft stopper (17) and collar,

@Remove the rest of the kickstarter from the lower
crankcase half,

Installation Notes:

1. To replace the kick spring, turn the shaft all the way
clockwise, insert one end of the spring into the crank-
case, insert the other end into the kick shaft, and,
while holding the spring in place, insert the kick

spring guide,

>

“ai _ x
_ Kick Spring

os

: tee y : - ‘
Kick Spring Guida Guide J x.

&

2, Be sure to bend back the ends of the ae over
the stopper bolts.

3, Apply a thin coat of heat durable grease to the inside
of the collar before replacement,

4, Punch the screws 76) after installing the kick shaft
slLopper.

64 DISASSEMBLY

Kickstarter

http://www.kz400.com/

3. Kick Spring

. Spring Guide
5. Kick Shaft
» Screw
. Kick Shaft Stopper
. Spring cap . Kick Pedal
. Spring 19. C Ring
. Ratchet Gear 20, Washer
. Circlip 21. Spring
|. Stopper Bolt 9%. Washer 22, Kick Pedal
2, Washer 10. Kick Gear 23, Pedal Rubber
3. Stopper ll. Kick Shaft Collar 24. Bolt
4. Circlip 12. Circlip 25, Circlip
Disassembly : (Pg. 56). The transmission itself does not require
ePull off the kick gear (0 and thrust washer (9), removal.

@Remove the circlip (@) on the spring side, and take
off the spring cap (5), and spring @).

ePull off the kick ratchet gear (7) .

@Remove the remaining circlip g@ .

Assembly Note:
@for replacing the ratchet gear, align the ratchet gear
punch mark with the notch on the kick shaft.

Punch Mark

OIL PRESSURE RELIEF VALVE
Removal:
eSplit the crankcase as explained in transmission removal

@Unscrew the valve from the lower crankcase half.

~— Oil Pressure Relief Valve

Installation Note:

eUse a non-permanent locking agent on the valve threads.
*NOTE: From engine number K4E095256 on for
KZ400D, and from K4SE027556 on for KZ400S, a ball
type relief valve is used in place of the piston type relief
valve. Do not disassemble the ball type relief valve for
inspection. Replacement parts are not available.

http://www.kz400.com/

eKemove the circlip, and take out the washer, spring,
and valve piston.
) '
28

Valve Piston

BALANCER MECHANISM

Removal:

eSplit the crankcase as explained in transmission removal
(Pg. 56). The transmission itself does not require
removal if only the balancer mechanism is to be re-
moved,

@Remove the bolts (4) and screws (2), and lift off the
crankshaft bushing cap. Tap lightly on the sides of the
cap with a plastic hammer if necessary to facilitate
removal,

@Remove the balancer chain guide from the chain.

7

S
[Balancer. Chain Guide
= a

oh,

@Remove the balancer mechanism holder bolts (8).
@/ap lightly on the sides of each holder, and then lift
off the entire balancer mechanism.

DISASSEMBLY 65

Installation:

eCheck to see that the holder O rings (4) and the pin
are all in place.

Hol der-sOaR ost

@lurn the crankshaft so that the crankshaft oj! holes
are even with the upper crankcase half surface with
the flywheels positioned up as shown in Fig. 252, If
necessary, temporarily replace the timing advancer and
use a 17 mm wrench to turn the crankshaft,

Crenkchat Omen a

eCheck to see that the mechanism is correctly assembled.
@Holding the chain taut, pick up the balancer mechanism,
place one of the units into position, and match the
sprocket punch mark with the line on the holder.
Keeping the chain in its proper position on the
sprockets, let the chain fall in place on the crankshatt
balancer sprocket, and fit the other unit into place.

y Plated Link

66 DISASSEMBLY http://www.kz400.com/

@Check to see that the chrome plated link aligns with
the holder line for each balancer unit, and that the
balancer weights face up, not cocked to either side.

— 254

en, Plated Link
e ~~

=e,

>, Plated Link
\w

—_—_ i ;,

®|f the weights are cocked to one side, alter the position
of the chain on the crankshaft balancer sprocket until
the weights are positioned properly.

@®Whenever the balancer unit are disassembled, replace
the balancer holder bolts with a new one, and tighten
the bolts for each unit with 2.3 ~ 2.7 (16.5 ~ 19.5
ft-lbs) of torque. Make sure that each holder fits all the
way down on its knock pins.

@Daub a little engine oil on the bushing halves on the
crankshaft bushing cap.

@Place the balancer chain guide into position, set the
crankshaft bushing cap into place with the arrow
pointing to the front, and then tighten the screws
(2) to secure the guide to the cap. Use a non-
permanent locking agent on the screws. A chain
guide and two bushing halves go with the cap.

®Tighten the bolts (4) in the sequence shown in Fig.
255 lirst to 1.5 kg-m (11 ft-lbs) of torque and then to

2.5~ 3.0 kg-m (18~ 22 ft-lbs),

= =

@Fit the crankcase as explained transmission installation
(Pg. 58).

Disassembly (per balancer unit):

@Remove the chain 12,

eSlide off each holder @) 4) and the shims @@.

elapping lightly with a plastic hammer, remove the
sprocket (5). The springs (8) and pins (7) (4 ea) may
be removed.

@fake out the balancer weight bolt @), and slide the
weight “0 off the shaft @.

Assembly (per balancer unit):

®Apply oil to the shaft, and insert it into the balancer
weight. Match the larger shaft hole with the hole in
the center of the weight, apply a non-permanent locking
agent to the bolt, and insert it. Tighten the bolt with
1.1~1.3 kg-m (95~ 113 in-lbs) of torque.

eWith the springs and pins (4 ea) all in place in the
inner circumference, replace the sprocket. The punch
mark on the sprocket must face out, and the sprocket
positioned as depicted in Fig, 256. Only one of the
four possible positions is correct.

Punch Mark 256)

Balancer Weight _

Sprocket

@Replace the shims on the sprocket side. The smaller
diameter shim goes on first.

@Replace the holders onto the shaft with the machined
side of each holder facing in.

®Replace the chain on the sprockets. For each sprocket,
the chrome plated link must fit on the sprocket tooth
with the punch mark, Also, the arrows on the holders
must point so that they will point away from the
crankshaft.

=

a Fey
Punch Mari

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os
‘. % f= 2
* i cet \

eed. 5 5

Plated Link Plated Link —

http://www.kz400.com/

Balancer Mechanism

|. Bolt

2, Holder 11. Holder

3, Shim 12. Balancer Chain

4. Shim 13. O Ring

5. Sprocket 14, Chain Guide

6. Balancer Shaft 15, Chain Guide

7, Pin 16. Crankshaft Bearing Cap
8. Spring l7. Screw

9, Balancer Weight Bolt 18. Bolt

10. Balancer Weight 19, Bolt

CRANKSHAFT, CAMSHAFT CHAIN

Removal:

®Remove the transmission (Pg. 56).

@Remove the balancer mechanism (Pg. 65),

@Remove any balancer mechanism holder O rings which

are loose.
@Remove the pin which holds the camshaft chain guide

pin in place.

DISASSEMBLY 67

\

Camshaft Chaing suide NY

. >

* B

@Replace the crankshaft bushing cap with its arrow
pointing to the front, and tighten its bolts (4),

@Remove the drive shaft set ring and output shaft set
ring.

@]urn the engine right side up.

@Remove the spark plugs,

@Remove the stud nuts (8), and pull off the cylinder
head cover. The cover has four O rings.

@Remove the chain tensioner cap and O ring.

68 DISASSEMBLY

@Remove the chain tensioner screws, and pull out the

a

entire tensioner assembly.

oe n

®Fit the timing advancer in place, and tighten its bolt.

®Remove the camshaft sprocket bolts (2), Use a 17mm
wrench to turn the crankshaft.

@Pull the sprocket off its position on the camshaft, slip
the chain off the sprocket, and remove the camshaft
and sprocket.

@Lift off the cylinder head and cylinder block assembly.

®Remove one of the piston pin snap rings from each
piston,

ins ee
Se

A,

®Remove each piston by pushing the piston pin out the
side the snap ring was removed. Use the piston pin
puller and adapter “B” (special tools) if necessary.

Piston Pin Puller
Tate

®Remove the timing advancer.

@/urn the upper crankcase half upside down.

@Remove the bolts (4), and take off the crankshaft
bushing cap.

http://www.kz400.com/

@Lift off the crankshaft, and remove the camshaft chain
and the oil seal,

Installation:

eCheck to see that all crankshaft bushing halves (4) are
in place, and daub a little engine oil on each bushing.

®Check that the wire band in the crankshaft oil seal has
nol slipped out of its proper position.

*®Fit the camshaft chain back on the lower camshaft
sprocket, place the oil seal on the dynamo end of the
crankshaft with the wire band side facing in, and set
the crankshaft back in its place on the upper crank-
case hall. The ridge on the oil seal must fit in its
crankcase groove,

=
Crankcase Groove

=

“SS ees

@Replace the crankshaft bushing cap with its arrow point-
ing to the front, and tighten its bolts (4),

®lurn the upper crankcase half right side up,

@Apply a little oil to the piston pins, and replace both
pistons and piston pins. The arrow on the top of each
piston must point towards the front.

®Fit a new piston pin snap ring into the side of each
piston.

@Fit the timing advancer on the end of the crankshaft,
and tighten its bolt.

®Apply a small amount of oil to the piston rings and
the inside of each cylinder.

Replace any of the cylinder base gasket or oil passage
O rings with a new one if deteriorated or damaged.
®Fit a piston base (special tool) on the crankcase opening
for each piston, and turn the crankshaft using a 17 mm
wrench such that each piston is situated squarely on its
piston base,

http://www.kz400.com/

DISASSEMBLY 69

Compress the piston rings using the piston ring com-
pressor assembly (special tool) for each piston.

268)

Piston Ring Compressor
57001-921

®Replace the cylinder block O rings with a new one
if it is deteriorated or damaged.

*Pull out the camshaft chain, and let it hang over the
side of the crankcase.

efit the cylinder head and cylinder block assembly on
the crankcase studs, guide the front camshaft chain
guide inside the block, and rest the bottom of the
cylinders on the piston ring compressors,

eLift up the camshalt chain, use a screwdriver to keep
the chain from falling down into the cylinder block,

eWork the bottom of each cylinder past the rings, and
set the assembly in place while removing the special
tools.

@Place the cylinder head holding plate (special tool) on
both sides of the cylinder head, and tighten both in
place using the stud nuts (8).

a
a

eSet the sprocket on the camshaft near where it fits.
The arrowed side of the sprocket faces the right side
of the engine.

®Run the camshaft through the camshaft chain from
the right side of the engine.

70 DISASSEMBLY

a Gear,Part

eTurn the crankshaft to where the timing advancer “T”
mark (the line adjoining the “T”) is directly up, Next,
turn the crankshaft counterclockwise exactly 90° (‘4
turn). At this point the “T" mark should align with
the upper crankcase half fitting surface,

aj

@furn the camshaft until the notch on the right end
faces directly up.

@lJurn the sprocket such that the arrow which has no
letter adjoining it points to the front of the engine
(points parallel to the cylinder head fitting surface),
and fit the chain on the sprocket.

http://www.kz400.com/

®Fit the sprocket up into place (the bolt holes will not
be aligned at this time), and turn the crankshaft while
holding the camshaft steady such that the bolt holes
align.

@Apply a non-permanent locking agent to one of the
sprocket bolts, and replace and tighten it with 1.4~
1.6 kg-m (10 ~ 11.5 ft-lbs) of torque.

eCheck that the timing advancer "T” mark and the
sprocket arrow are still properly positioned.

e@lfurn the crankshaft 180°, and replace the other sprocket
bolt. Use a non-permanent locking agent, and tighten
with 1.4~1.6 ke-m (10~ 11.5 ft-lbs) of torque.

@Remove the stud nuts (8), and remove the cylinder
head holding plates.

®Remove the tachometer gear (KZ400D) and the cylin-
der head cover caps (2) from the cylinder head cover.

eTurn the crankshaft to where the timing advancer
“1” mark is directly up,

@Apply liquid gasket to the cylinder head cover O ring
fitting surface if necessary to hold the O ring to the
cylinder head cover. Check that all O rings (4) are in
place,

@Place the cylinder head cover on the cylinder head,
and replace the nuts (8), Tighten them in the sequence
shown in Fig. 278, tightening first each nut to 1.5
kg-m (11 ft-lbs) of torque and then to 2.5 ~ 3.0
kg-m (18 ~ 22 ft-lbs).

@Check to see that the 8 mm cylinder head bolts are
at 2.5 ~ 3.0 kg-m (18 ~ 22 ft-lbs) of torque and the
6 mm bolts at 1.1 ~ 1.3 kg-m (95 ~ 113 in-lbs).

http://www.kz400.com/ DISASSEMBLY 71

Cylinder Head, Cylinder Head Cover Tightening Order 3. If a new crankshaft and/or connecting rod is used,
select the right bushing in accordance with the com-
bination of the connecting rod and the crankshaft
marks (Fig. 280, 281).

Ae Nil en ee
V2 OW WO),

(“\ I

Table 1 Bushing Selection

if Con-Rod =
Crank- ——~__ marking |
shaft marking Unmarked

| Black Brown
PN 13034-037 | PN 13034-048 |
Unmarked Blue Black
| | PN13034-047 | PN 13034-0037]

@Apply a small amount of heat durable grease to the
tachometer gear, and replace the tachometer gear and
the cylinder head cover caps (KZ400D),.

®feplace the tensioner assembly, The sequence is push
rod, spring, gasket, holder, push rod guide, and lock
nut, Tighten its screws, adjust it (Pg, 15), and replace
the cap and O ring,

@Replace the spark plugs,

@lurn the engine upside down,

@Replace the drive shaft set ring and output shaft set
ring,

@Remove the crankshaft bushing cap. |

@Replace the pin which holds the camshaft chain guide 28)
pin in place,

@Replace the balancer mechanism holder O rings which
were removed. :

einstall the balancer mechanism (Pg. 65).

einstall the transmission (Pg. 58),

Disassembly |
Remove the nuts (4) and connecting rods (2). Each /___ Color Mark

connecting rod has a bushing half in its big end.

Assembly Notes:

|. Fit the connecting rod big end together so that the
marks align.

CAMSHAFT CHAIN GUIDE (FRONT)
Removal:

@Remove the crankshaft (Pg. 67),

®Push the pin out, and remove the guide.

‘Chain Guide

2. Apply oil to the connecting rod big end bolts.
Tighten the nuts first loosely and then tighten each
nuts with 3.5 ~ 3.8 kg-m (25~27 ft-lbs) of torque.

72 DISASSEMBLY

Assembly Note:
@[he grooved end of the pin goes to the dynamo side,

CAMSHAFT CHAIN GUIDE (REAR)
Removal:

@Remove the cylinder block (Pg, 40).
@Remove the camshatt chain guide upper pin, and
remove the guide.

ty

ty "T
ts]
= a

mshaft Chain Guide (284)

hats!

FRONT WHEEL (Only on KZ400D)
Removal:

@#Put the motorcycle up on its center stand, and jack
or prop up the engine so that the front wheel will be
off the ground,

@®kemove the axle cotter pin, nut, and washer,

@®Remove the front axle clamp nuts (2), lock washers
(2), and clamp.

@Holding the wheel to facilitate axle removal, pull out
the axle, and then remove the wheel from the motor-
cycle. The speedometer gear housing easily separates
from the hub.

Installation:

eWith the speedometer cable running above the fender
slay, fit the speedometer gear housing into the hub,
hold the front wheel in its place between the front
shock absorbers, and insert the axle from the disc side,

http://www.kz400.com/

r ’
Fi it
* i
. o 1.
4 |
ry i Ti 7

]Speedo meter, Gear}t ousing}

@Replace the axle clamp, tightening it loosely. The
clamp must be positioned so that the arrow on the
bottom points to the front. Each nut has a lock washer.

=
+ =

®Replace the axle washer and nut. Tighten the axle
nut with 7~9 kg-m ($1 ~65 ft-lbs) of torque while
making sure that the speedometer gear housing does
not move out of its proper position.

®/nstall a new axle cotter pin.

®lTighten the axle clamp nuts, first the front one and
then the rear with 1.6~ 2.2 kg-m (11.5~ 16 ft-lbs) of
torque. [he front end of the clamp is the one which
fits squarely on the bottom of the fork outer tube.

Speedometer Gear Housing Disassembly:
@Disconnect the lower end of the speedometer cable
with pliers,

@Pull oul the speedometer gear 48 with close-in circlip
pliers or some other suitable tool,

Speedometer Gear

@lo remove the speedometer gear bush or speedometer
pinion, first drill out the pin in the speedometer gear
housing,

http://www.kz400.com

Front Hub (KZ400D)

. Grease Seal

l. Front Axle 12. Speedometer Gear Housing
2. Bolt 13. Pin

3. Double Washer l4. Washer

4. Cap 15. Speedometer Pinion

5. Disc lo. Bush

6. Front Hub 17. Gear Drive

7. Grease Seal 18. Speedometer Gear

8. Circlip 19. Axle Nut

9. Ball Bearing 20, Cotter Pin

10. Distance Collar 21. Ball Bearing

Speedometer Gear Housing Assembly Notes:

1. Regrease the speedometer gear (Pg, 138).

2. Insert the speedometer inner cable into the housing
while turning the gear so that the slot in the end of
the cable will seat in the tongue of the speedometer
pinion,

Front Hub Disassembly: .

eStraighten back the part of the disc double washers
(3) that are bent over the disc bolts (2), remove the
bolts (4) and double washers (2), and pull off the disc
6).

ePull off the cap (@) on the disc side of the hub,

@Pull out the grease seal (7) on the disc side using a
hook, and remove the circlip (@).

@lnsert a metal rod into the hub from the speedometer
gear side, and remove the bearing () on the disc side
by lapping evenly around the bearing inner race.

DISASSEMBLY 73

[Metall od rr

@Remove the remaining grease seal @) using a hook,
and pull oul the speedometer gear drive 47).

@lnsert the metal rod into the hub from the disc side,
and remove the other bearing @) by tapping evenly
around the bearing inner race, The distance collar
(0) will come out with the bearing.

http://www.kz400.com

74 DISASSEMBLY

Front Hub Assembly Notes:

1. Inspect the bearings and replace if necessary (Pg. 138).
Install them using the wheel bearing driver “A” and
ihe bearing driver holder (special tools).

i
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——s

570015139 a

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: . SS ..

i ——
! a —— . - & a. Po ,
=~ Wheel ‘Bearing, Driverds

a

2. Replace the grease seals with new ones using a press
or wheel bearing driver “A” (special tool),

3. lighten the dise bolts (4) with 1.6~ 2.2 kg-m (11.5
~ 16 ftlbs) of torque, bend the washer tabs back
over the disc bolts,

4. Clean off completely any grease that has gotten on
either side of the disc with a high flash point solvent
of some kind. Do not use one which will leave an
oily residue.

FRONT WHEEL (Only on KZ400S)

Removal:

ePut the motorcycle up on the jack or block, and jack
or prop up the engine so that the front wheel is off
the ground.

@Remove the cotter pin from the threaded brake cable
extension, screw off the adjusting nut, and free the
brake cable from the brake panel, Also remove the
brake cable joint,

ay \) f/ TA

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1!
‘a, © ) Ae ,
— J a _
*,.
J = ' — =
— ‘ = a

@®Kemove the speedometer cable bolt and washer and
pull the lower end of the speedometer cable off the
brake panel.

e@lake out the torque link clips, remove the nuts (2),
bolt, lock washers (2), and remove the torque link.

atl

an WY PA .

@Remove the front axle cotter pin, nut and washer,

@Remove the front axle clamp nuts (2), lock washers
(2), and clamp.

eHolding the wheel to facilitate axle removal, pull out
the axle, and then remove the wheel from the motor-
cycle,

Installation:

@Hold the front wheel in place between the front shock
absorbers, and insert the axle from the brake panel side.

@®Replace the axle clamp, tightening it loosely. The
clamp must be positioned so that the arrow on the
bottom points to the front, Each nut has alock washer.

@Replace the axle washer and nut, tightening it loosely.
@Replace the torque link, and replace its bolt, lock
washers (2), and nuts (2).

@lTighten the torque link nuts with 2.6 ~ 3.5 kg-m
(19 ~ 25 ft-lbs) of torque, and replace the torque
link clips.

http://www.kz400.com

®Tighten the axle nut with 7 ~ 9 kg-m (51 ~ 65
ft-lbs) of torque, and install a new axle cotter pin.
®Tighten the axle clamp nuts, first the front one and
then the rear with 1.6 ~ 2.2 kg-m (11.5 ~ 16 ft-lbs)
of torque.
eWith the speedometer cable running above the fender
slay, insert the speedometer inner cable into the front
brake panel while turning the wheel so that the inner
cable end will seat in the speedometer pinion gear.
Replace the speedometer cable bolt and washer,
eWith the brake cable running in the same manner as
the speedometer cable, attach the brake cable, brake
cable joint, and adjusting nut back onto the front
brake panel. Replace a new cotter pin at the end of
the threaded brake cable extension,

@Adjust the front brake (Pg, 17).

Front Brake Disassembly:
WARNING:Brake linings contain asbestos fiber. Inhala-
tion of asbestos may cause serious scarring of the lungs
and may promote other internal injury and illness, in-
cluding cancer. Observe the following precautions when
handling brake linings:
1. Never blow brake lining dust with compressed air.
2. If any components are to be cleaned, wash with
detergent, then immediately discard the cleaning
solution and wash your hands.
3. Do not grind any brake lining material unless a ven-
tilation hood is available and properly used.
@Pull out the axle ‘T) and remove the brake panel 35 .
Using a clean cloth around the linings if necessary to
prevent grease or oil from getting on them, remove the
brake shoes (22) by pulling them off the brake cam
shafts 18).

Pull shoe

DISASSEMBLY 75

®Remove the brake spirngs 23 (2) to separate the two
brake shoes.

@Mark the position of each cam lever 13 on the camshaft
so that they can later be installed at the same angle.

@Remove the cam levers, return spring, brake lining wear
indicator 15), washer (9), and gaskets 10).

®Remove the camshafts,

®/o remove the speedometer pinion gear 20, unscrew
the speedometer pinion gear bushing 2) from the brake
panel, and drop out the pinion gear and washers 72,

Front Brake Assembly:

®Grease the speedometer pinion gear, replace the pinion
gear and its washers, and screw in the speedometer
pinion gear bushing securely.

®Clean the old grease from the camshafts and anchor
pins, and regrease them using regular cup grease (Pg,
147).

®/nstall the brake springs connecting the brake shoes,

®Wrapping a clean cloth around the linings if necessary
lo prevent grease or oi] from getting on them, put the
shoes back onto the brake panel.

@/it the gaskets on the camshafts.

@Replace the washer and the brake lining wear indicator.
The indicator should point just to the right of the “E”
in RANGE,

Usable Range

76 DISASSEMBLY
Front Hub (KZ400S)

@Replace the cam levers with the return spring part of
the way onto the camshafts, fit the return spring end
into its hole in the panel, and put the cam levers the
rest of the way into position on the camshafts. Tighten

the bolts,

Return Spring

Spring Hole

@Adjust the front brake (Pg, 17).

http://www.kz400.com

Front Hub Disassembly
ePull off the brake panel 35) and axle (1).

e@Pull off the cap 31).

@Pull off the grease seal 30 on the cap side using a hook.

Sa ee oe algae ein Ls sand

©

Axle

Pin

Joint

Lock Nut
Connecting Rod
Joint

Nut

Cotter Pin
Washer
Gasket
Return Spring
Bolt

., Primary Cam Lever
. Secondary Cam Lever

Indicator

. Bolt

. Washer

. Camshaft
. Washer

Speedometer Pinion Gear

. Bush

Brake Shoe

. Spring

. Speedometer Gear
. Grease Seal
. Ball Bearing
. Collar

. Front Hub
. Ball Bearing
. Grease Seal
. Cap

. Washer

. Axle Nut

. Cotter Pin

. Brake Panel

http://www.kz400.com

@®|nsert a metal rod into the hub from the cap side,
and remove the bearing (26) by tapping evenly around
its inner race. The distance collar 27) will come out
with the, bearing.

®lnsert a metal rod into the hub from the panel side,
and remove the bearing 29) on the cap side by tapping
evenly around its inner race.

®lo remove the grease seal 25) on the panel side, pull off
the speedometer gear using a gear puller, and pull off
the grease seal using a hook.

Front Hub Assembly Notes:

|, Insepet the bearings and replace them if necessary
(Pg, 138). Install them using wheel bearing driver
“A” and the bearing driver holder (special tools).

Bearing Driver Holder @a

§57001-139 =

es

Pa

Wheel:B aring Driver Ags -F
457 001-288 j

Ax

a

=

>

—=

2. Put in new grease seals using a press or wheel bearing
driver “A” (special tool).

3. After installing the speedometer gear, punch four
points on the drum to lock the gear in place.

4, Regrease the speedometer gear (Pg. 138),

DISASSEMBLY 77

REAR WHEEL
Removal:

@Put the motorcycle up on its center stand.

@fake out the clip from the rear torque link bolt,
remove the nut and lock washer, and free the torque
link from its bolt.

eBeing careful not to bend or otherwise damage it,
free the rear brake light switch spring from the tab
on the brake pedal.

@®Remove the adjusting nut from the end of the brake
rod, and then free the rod from the cam lever by
depressing the brake pedal. Remove the brake rod
spring and joint.

Joint —

a

F rake Rod

@®lake out the cotter pin, remove the axle nut and
washer, and pull out the axle.

eRemove the axle sleeve from the right side of the wheel,

eSlide the wheel out of the wheel coupling and then free
from the motorcycle.

Installation:

eCheck to see that the torque link bolt is in place in
the brake panel, and slip the wheel back into the
coupling.

@Replace the axle sleeve.

@®Slide the axle through the hub from the left to the
right,

e@Fit the torque link onto its bolt, and replace its lock
washer and nut.

®Tighten the torque link nut with 2.6 ~ 3.5 kg-m (19~
25 ft-lbs) of torque, and replace its clip.

78 DISASSEMBLY http://www.kz400.com

@Replace the axle washer and nut, tightening the nut
to 10~14 kg-m (72~101 ft-lbs) of torque.

@lnstall a new axle cotter pin.

@®Keplace the joint into the end of the cam lever and
the spring on the end of the brake rod.

@Fit the rod through the joint, andscrewon the adjuster.
@Carefully fit the rear brake light switch spring back into
the tab on the brake pedal.

eAdjust the rear brake (Pg. 19), and check the rear
brake light switch adjustment (Pg. 20).

77
a a ee
©

Rear Brake Disassembly:

NOTE: Refer to the warning (Pg. 75) for general brake
information.

®Remove the brake panel @0) from the wheel.

@Mark the position of the cam lever 43 on the camshaft @®Remove the cam lever, brake lining wear indicator 42,
(0 so that it can later be installed at the same angle. and gasket (i) .
Rear Hub

Axle

. Bearing

. Distance Collar
Shock Damper Rubber
Bearing

Cotter Pin

. Double Washer

. Brake Shoe

. Spring

. Camshaft

Gasket

. Brake Lining Wear Indicator
. Cam Lever

. Bolt

. Axle Sleeve _
. Washer (4)

. Axle Nut
18. Cotter Pin
19, Sprocket
20, Nut
21, Double Washer
22. Coupling Sleeve Nut
23, Washer
24, Collar
25. Grease Seal
26. Bearing
27, Coupling Sleeve
28. Bolt
29, Rear Hub
30, Brake Panel
31. Wheel Coupling
32, O Ring

http://www.kz400.com

@Pull out the cotter pins @) (2), and take off the double
washer (7) .

eUsing a clean cloth around the linings if necessary to
prevent grease or ojl from getting on the linings, pull
the brake shoes (8), spring 9), and camshaft as an
assembly off the brake panel.

®]wist the brake shoes as shown in Fig, 310 to separate
the camshaft from the shoes,

Brake Shoes

@®Remove the spring to separate the brake shoes.

Rear Brake Assembly:

eClean the old grease from the camshaft, and regrease
using regular cup grease. Apply grease to the center
of the shaft and on the cam surfaces. Do not over-
grease,

DISASSEMBLY 79

®/nstall the spring connecting the brake shoes.

®Wrapping a clean cloth around the linings if necessary
to prevent grease or oil from getting on the linings,
fit the camshaft between the brake shoes, and then
fit the assembly back onto the brake panel.

@Replace the double washer (7) on the anchor pins, and
install new cotter pins © (2).

@Fit the gasket on the camshaft.

@Replace the brake lining wear indicator so that it points
just to the right of the “E” in RANGE.

7 \ Brake | lining Wear Incitatot
MS 77

@Replace the cam lever into its original position on the
camshaft, and tighten its bolt,

eCheck to see that the torque link bolt ts in place in
the panel, and fit the panel back into the wheel.

Rear Hub Disassembly:

ePull off the brake panel 30 .

@/nsert a metal rod into the hub, and remove the bearing
(2) on the other side by tapping evenly around the
bearing inner race. The distance collar 3 will come
out with the bearing.

@lnsert the metal rod into the hub from the other side,
and remove the remaining bearing (5) by tapping evenly
around the bearing inner race,

Rear Hub Assembly Notes:

1. Inspect the bearings and replace if necessary (Pg, 138).
Install them using the wheel bearing driver “C” and
the bearing driver holder (special tools).

Bearing Driver Holder —

oa 290

2. Inspect the O ring and replace if necessary,

http://www.kz400.com

80 DISASSEMBLY

TIRE, TUBE
Removal:

@Remove the wheel from the motorcycle (Pg. 72 or
74 Or 7a):

@®Mark the valve stem position on the tire with chalk
so that the tire will not get turned and upset wheel
balance.

@®]ake out the valve core to let out the air,

@Remove the valve stem nut,

@Use a rubber mallet to break the tire beads away from
both sides of the rim.

@Step on the side of the tire opposite the valve stem,
and start prying the tire off the rim near the valve
stem with tire irons. Take care not to insert the tire
irons so deeply that the tube gets damaged.

@Remove the tube when one side of the tire is pried off,
ePry the tire off the rim.

Installation:

@Put just enough air in the tube to keep it from getting
caught between the tire and rim, and insert it into the
lire at this point, even if the tire was completely
removed from the rim, Insert the valve stem into
the rim, and screw the nut on loosely.

elf the tire was completely removed, pry one side back
onto the rim. Align the chalk mark on the tire with
the valve stem.

ePry the other side of the tire onto the rim, starting
at the side opposite the valve. Take care not to insert
to the tire irons so deeply that the tube gets damaged.

eCheck that the tube is not pinched between the tire
and rim, and then inflate to the standard pressure (Pg.
133).

@lighten the valve stem nut, and put on the valve cap.
eBalance the wheel (Pg. 17).

@Mount the wheel back onto the motorcycle (Pg. 72 or
74 or 77).

RIM

Removal:

@Remove the wheel from the motorcycle (Pg. 72 or
74 or 77).

@lake the tire and tube off the rim (Pg. 80).

@lape or wire all the spoke intersections so that the
spokes don’t get mixed up, and unscrew the nipples
from all the spokes with a screwdriver.

lf

Installation:

@Fit all the spokes through the holes, and screw all the
nipples onto the spokes tightening them partially,

eSuspend the wheel by the axle, and set up a dial gauge
to measure fim runout,

®Tighten the spokes evenly so that the radial (out from
the axle) runout is less than 0.8 mm and the axial (side
to side) runout is less than 0.5 mm.

@®Make sure that the spokes are tightened evenly.
Standard torque is 0.2 ~ 0.4 kg-m (17 ~ 35 in-lbs).

eMount the tube and tire (Pg. 80),

@Balance the wheel (Pg. 17).

eMount the wheel back onto the motorcycle (Pg. 72 or
74 or 77). |

SPOKE (breakage replacement)
@Reduce the tire air pressure by a small amount,

http://Awww.kz400.com

@insert the new spoke through the hub, and bend it to
meet the nipple.

@Tighten with a spoke wrench. Standard torque is 0.2~
0.4 kg-m (17~35 in-lbs).
@lnflate the tire to standard pressure (Pg, 133).

DISC BRAKE (Only on KZ400D)

Removal, installation, disassembly, and assembly of
the disc brake is divided up as follows:
Pad Removal Caliper Assembly
Pad Installation Master Cylinder Removal
Disc Removal Master Cylinder Installation
Disc Installation Note Notes
Caliper Removal Master Cylinder Disassembly
Caliper Installation Note Master Cylinder Assembly
Caliper Disassembly Notes

Before working on the disc brake, take speciai note
of the following:
WARNING:Brake linings contain asbestos fiber. Inhala-
tion of asbestos may cause serious scarring of the lungs
and may promote other internal injury and illness, in-
cluding cancer. Observe the following precautions when
handling brake linings:
1. Never blow brake lining dust with compressed air.
2. If any components are to be cleaned, wash with
detergent, then immediately discard the cleaning
solution and wash your hands.
3. Do not grind any brake lining material unless a ven-
tilation hood is available and properly used.

CAUTION

1. Except for the disc pads and disc, use only disc brake
fluid, isopropyl alcohol, or ethyl! alcohol for cleaning
brake parts. Do not use any other fluid for cleaning
these parts, Gasoline, motor oil, or any other petrol-
eum distillate will cause deterioration of the rubber
parts. Oil spilt on any part will be difficult to wash
off completely, and will eventually reach and break
down the rubber used in the disc brake.

2. When handling the disc pads or disc, be careful that
no disc brake fluid or any oil gets on them. Clean
off any fluid or oil that inadvertently gets on the pads
or disc with a high flash point solvent of some kind.
Replace the pads for new ones if they cannot be
cleaned satisfactorily.

3. Brake fluid quickly ruins painted surfaces: any spilt
fluid should be completely wiped up immediately.

Table 2

Disc mounting bolts

DISASSEMBLY 81

4. \f any of the brake line fittings or the bleed valve is
opened at any time, AIR MUST BE BLED FROM
THE BRAKE (Pg. 143).

5. When installing or assembling the disc brake, tighten
the disc brake fittings to the values given in Table 2.
Improper torque may cause the brake to malfunction.

Disc Brake Torque
0.5~0.7 kg-m | 43-~61 in-Ibs
1.8~2.3 kg-m | 13.0~16.5 ft-lbs

0.6~0.9 kgm | 52~78 in-Ibs
2.9~3.1 kg-m | 21~22 ft-Ibs
1.7~1.9 kg-m | 12,0~13.5 ft-lbs
0.5~0.6 kg-m | 43~52 in-Ibs

Brake lever pivot bolt
Brake lever adjusting
bolt lock nut
Master cylinder clamp
Fitting (banjo) bolts
Brake pipe nipple

3-way joint

| Front brake light switch | 2.6~3.0 kg-m | 19~22 ft-lbs

Caliper shafts
Caliper mounting bolts
Bleed valve

3.0~3.6 kg-m | 22~26 ft-lbs
3.4-4.6 kgm | 25~33 ft-lbs
0.7-~1.0 kg-m | 61~85 in-Ibs
1.8~2.0 kg-m | 13.0~14.5 ft-lbs

Pad Removal:

@Remove the front wheel (Pg. 72).

@/ake out the mounting screw for pad B, and remove
the pad. A lock washer and metal disc also come off.

cw
—_—

®Alter pad B ts removed, squeeze the brake lever several
times until the piston pushes out pad A.

Pad Installation:

@®Remove the bleed valve cap, open (loosen) the valve
slightly, push the piston in by hand as far as it will
go, and then close (tighten) the valve. Wipe up any
spilt fluid, and recap the bleed valve.

Bleed Valve

®@Fit to the rear of pad A the anti-squeak shim, align
the projection of pad A with the slot in the bottom
of the caliper, and insert the pad.

82 DISASSEMBLY

\, Projection

Anti-squeak Shim

®/nstall pad B, its metal disc, mounting screw, and lock
washer, Use a non-permanent locking agent on the
mounting screw.

@Since fluid was spill when the bleed valve was opened,
check the fluid level in the master cylinder.

Disc Removal:
®Remove the front wheel (Pg. 72).
eStraighten back the portions of the disc double washers
2) that are bent over the disc bolts (1), and remove the
bolts (4) and double washers (2).
@ePull off the disc (3).

Disc Installation Note:
®Tighten the disc bolts with 1.8 ~ 2.0 kg-m (13.0~14.5

ft-lbs) of torque, bend the washer tabs back over the
disc bolts.

Caliper Removal:

eUnscrew the brake pipe from where it connects to the
caliper. Cap the end of the pipe to prevent fluid from
flowing out,

Disc (KZ400D)

http://www.kz400.com

e|f the caliper holder is to be removed, loosen the Allen
bolts (2) now.

@Remove the mounting bolts (2), each with a flat washer
and lock washer, and then take off the caliper.

Installation Note:

Bleed the brake line after installation (Pg. 143).

Caliper Disassembly:

eCover the caliper opening with clean, sturdy cloth, and
remove the piston (2) by applying compressed air to
where the brake line fits into the caliper.

323)

2)

|. Bolts
2. Double Washers
3. Disc

http://www.kz400.com

Caliper Assembly

|. Caliper 12. Dust Cover

2, Piston 13. O Ring

3. Fluid Seal 14. Caliper Holder
4. Piston Dust Seal 15. Bolt

5, Anti-squeak Shim 16, Lock Washer

6. Pad A 17. Washer

7. PadB 18. Allen Bolt

8. Metal Disc 19. Bleed Valve

9, Lock Washer 20. Bleed Valve Cap
10. Screw 21. Spring Plate

@/aking ample care not to damage the cylinder surface,
remove the piston dust seal ) and fluid seal (3) care-
fully with a hook.

@Remove the caliper holder Allen bolts 8 (2) .

@Pull out the caliper holder 14, and pry off the clip
1) and dust cover 12).

Caliper Assembly:

@Clean the caliper parts with brake fluid or alcohol (See
CAUTION—Pg, 81).

efit the dust cover onto the caliper holder with the
outside of its inner lip in the groove on the holder,
and then fit the inside of the outer lip into the groove
on the caliper. Be sure that the lips fit in place evenly.

@/nstall the clip.

eWith the caliper holder properly positioned, replace and
tighten its Allen bolts,

@Fit the fluid seal and dust seal in place inside the
cylinder.

@®Apply brake fluid to the outside of the piston, and
press into place with a press, the inside of the piston
facing out, Take care that neither the cylinder nor
the piston skirt get scratched,

DISASSEMBLY 83

e@Fit to the rear of pad A the anti-squeak shim, align
the projection of pad A with the slot in the bottom
of the caliper, and insert the pad.

@install pad B, its metal disc, mounting screw, and lock
washer, Use a non-permanent locking agent on the
mounting screw,

84 DISASSEMBLY
Disc Brake (KZ7400D)

http://www.kz400.com

Cap

Plate
Diaphragm
Brake Lever

. Dust Seal Stopper

. Dust Seal

. Retaining Ring

. Piston Stopper

. Piston Assembly

. Primary Cup

. Spring Assembly

. Check Valve Assembly

. Secondary Cup

. Bolt

. Nut

. Lock Washer

. Nut

. Bolt

. Bolt

. Washer

. Master Cylinder Clamp
. Master Cylinder Body
. Washer

. Banjo Bolt

25.
26.
27.
28,
29,
30),
Se
32.
33,
34,

Dust Cover
Hose

Grommet
Pressure Switch
3-Way Fitting
Pipe

Bolt

Bolt

Washer

Hose

http://www.kz400.com

Master Cylinder Removal:

@lake off the right rear view mirror.

@Pull back the dust cover, and remove the banjo bolt
Lo disconnect the upper brake hose from the master
cylinder. There is a flat washer on each side of the
hose fitting.

®Remove the clamp bolts (2), and take off the master
cylinder, There is a flat washer for each master cylinder
clamp bolt. Wipe up immediately any brake fluid that
spills.

Master Cylinder Installation Notes:

|. The master cylinder clamp is installed with the small
projection towards the throttle grip. Tighten first the
upper clamp bolt and then the lower clamp bolt, both
with 0,6~ 0,9 kg-m ($2~78 in-lbs) of torque.

Master Cylinder Clamp

Projection

2, Bleed the brake line after master cylinder installation
(Pg. 143).

Master Cylinder Disassembly:

@®lJake off the master cylinder cap 4
3, and empty out the brake fluid.

@lake off the brake Jever (4). Use the master cylinder

and diaphragm

stopper remover (special tool) to remove the dust seal
stopper (5

, and then remove the dust seal (6

SS foe Seal) kopper

Master Gy inder Stopper Remover
56019-1171

eRemove the retaining ring (7) with retaining ring pliers
(special tool), and take the stopper (8) , piston @) ,
primary cup (9), spring 4), and check valve (12 out of

DISASSEMBLY 85

the master cylinder body. Do not remove the second-
ary cup 13: from the piston since removal would damage
the cup.

\ Piston

a

| Retaining Ring

Master Cylinder Assembly Notes:

l.

ho

Before assembly, clean all parts including the master
cylinder with brake fluid or alcohol (See CAUTION—
Pg. 81), and apply brake fluid to the removed parts
and to the inner wall of the cylinder.

. Be sure that the primary cup and check valve are not
installed backwards and that neither is turned side-
ways after insertion,

3, Use a new retaining ring for assembly, pushing it into

place in the cylinder wall groove with the master
cylinder ring driver (special tool). Use the same tool
for installing the dust seal and dust seal stopper.

DRIVE CHAIN
Removal:
A. lf the chain is being removed and replaced again for

cleaning or engine removal:

®Check to see that the transmission is in neutral.
@lake oul the shift pedal bolt and remove the shift

pedal.

@®Remove the left foot peg bolt, left foot peg, and side

stand spring.

@Remove the engine sprocket cover screws (4), and pull

the cover out of place.

@Remove the clip carefully from the drive chain master

link with pliers, and remove the master link,

86 DISASSEMBLY

®Remove the drive chain from the sprockets,

B. If the chain is being replaced with a new chain:

eCheck to see that the transmission ts in neutral.

®Remove the clip from the drive chain master link with
pliers, and remove the master link.

@Fit the new chain on the end of the old chain with the
master link,

Installation:

@/-it the original chain back on the engine sprocket or
pull the new chain onto the engine sprocket by pulling
the old one off, Set the ends of the chain on the rear

http://www.kz400.com

matches the level of the dynamo cover lower right
screw.

@eAdjust the chain if necessary (Pg. 20).

REAR SPROCKET, WHEEL COUPLING

Removal:

@Put the motorcycle up on its center stand.

@Take out the clip from the rear torque link bolt, remove
the nut and lock washer, and free the torque link from

sprocket as shown in Fig, 333. its bolt,

eBeing careful not to bend or otherwise damage it, free
the rear brake light switch spring from the tab on the
brake pedal.

@Remove the adjusting nut from the end of the brake
rod, and then free the rod from the cam lever by
depressing the brake pedal. Remove the brake rod
spring and joint.

@lake out the cotter pin, remove the axle nut and
washer, and pull out the axle.

@®Remove the axle sleeve from the right side of the
wheel,

@Position the chain on the rear sprocket so that the
drive chain master link is at the rear.

@eRemove the clip carefully from the drive chain master
link using pliers, and then remove the master link

@lnstall the chain master link with pliers. The direction
of the master link clip should be as shown in Fig. 334,

_ Masterglfink Clip
' | - — =—= =
— ~~ =

@lurn the rear wheel so that the rear sprocket will be
free from the chain.

@Remove the coupling sleeve nut and washer.

e@Slide the rear wheel together with the sprocket and
coupling free from the motorcycle.

@Straighten back the portions of the rear sprocket
washers that are bent over the sprocket nuts,

@Replace the engine sprocket cover (if removed) using
the shift shaft oil seal guide (special tool) to protect
the oil seal in the cover, and tighten its screws.

efit the side stand spring (if removed) into place, and
then secure the left foot peg with its bolt,

@®Replace the shift pedal (if removed) so that its end

http://www.kz400.com

eRemove the rear sprocket nuts (4), the sprocket double
washers (2), and the sprocket bolts to separate the rear
sprocket and wheel coupling.

Installation:

@/nsert the sprocket bolts, and replace the rear sprocket,
double washers, and nuts, Tighten the nuts with 3.5
~ 4.3 kg-m (25 ~ 31 ft-lbs) of torque and bend the
Washers back over the nuts.

eCheck to see that the torque link bolt is in place in
the brake panel, and slip the wheei into place inserting
the coupling sleeve through the left chain adjuster and
left side of the swing arm.

®Position the wheel far enough forward to facilitate
chain installation, and replace the coupling sleeve flat
washer and nut,

®Replace the axle sleeve.

@Slide the axle through the hub from the left to the
right,

eFit the drive chain back onto the rear sprocket, and
set the ends into the position shown in Fig. 337.

@Replace the chain master link using pliers. The direction
of the master link clip should be as shown in Fig, 338.

Master(Eink Clip

®Loosen the coupling sleeve nut, and adjust the chain
with the left and right chain adjusters so that the chain
will have a maximum of about 20~25 mm of vertical
movement at its greatest point, To keep the chain and
wheel aligned, the notch in the left chain adjuster must
come to the same swing arm mark that the right chain

DISASSEMBLY 87

adjuster notch comes to.

@/ighten the coupling sleeve nut securely,

@Recheck the chain tension, and readjust if necessary.

@Fit the torque link onto its bolt, and replace its lock
washer and nut,

eTighten the torque link nut with 2.6~3.5 kg-m (19~

25 ft-lbs) of torque, and replace its clip.

@Replace the axle washer and nut, tightening the nut to
10~14 kg-m (72~101 ft-lbs) of torque.

@/nstall a new axle cotter pin,

@Replace the joint into the end of the cam lever and
the spring on the end of the brake rod.

e@Fit the rod through the joint, and screw on the adjuster.

eCarefully fit the rear brake light switch spring back into
the tab on the brake pedal.

@Adjust the rear brake (Pg. 19 ), and check the rear
brake light switch adjustment (Pg. 20).

Coupling Disassembly:

@Pull out the sleeve, and pull off the collar.

@Pull out the grease seal using a hook,

®|nsert a metal rod into the wheel side of the coupling,
and remove the bearing by tapping evenly around the
bearing inner race.

Coupling Assembly Notes:

|. Replace the grease seal with a new one using the
wheel bearing driver “B” and the bearing driver holder
(special Lools),.

Bearing'D Driver. ? Holders

57001-139aay _—, (Za

whieel Bearing Dri ver i Bsc

ene

7001 -289

a ‘Ss —

2. Inspect the bearing, and replace if necessary (Pg. 138).
Lubricate it (Pg. 138), and install it using the wheel
bearing driver “B” and the bearing driver holder
(special tools),

88 DISASSEMBLY

HANDLEBAR

Removal:

@Remove the clutch adjusting cover,

eloosen the lock nut, and back out the clutch adjusting
screw to give the clutch cable plenty of play.

) a W ay ;

®lake off the rear view mirrors.

@loosen the lock nut on the clutch lever, and screw
In the adjuster,

®Linc up the slots in the clutch lever, lock nut, and
adjuster, and free the inner cable from the lever.

2

@Remove the strap which holds the light switch wiring
harness to the handlebar and the strap which holds
the engine stop switch wiring harness to the handlebar.

@fake out the light switch screws (2), and remove the
light switch from the handlebar.

®Remove the engine stop switch housing screws (2), and
open up the housing,

@Loosen the master cylinder clamp bolts (2) (KZ400D),

@oosen the front brake lever bolt (KZ400S),

@Remove the handlebar clamp bolts (4), remove the
clamps (2), and slide the handlebar from the master
cylinder and the engine stop switch and throttle grip

assembly,

— CE iPibolts

http://www.kz400.com

@!o remove the clutch lever, loosen the clutch lever
bolt, cut off the left handlegrip, which is bonded to
the handlebar, and slide off the clutch lever.

Installation:

elf the clutch lever and left handlegrip were removed,
slide the clutch lever back on, tighten its bolt with
the lever at the proper angle, and bond a new left
handlegrip onto the handlebar.

@Slide the right side of the handlebar through the master
cylinder holder into the engine stop switch housing and
throttle grip assembly (KZ400D),

@Slide the right side of the handlebar through the front
brake lever into the engine stop switch housing and
throttle grip assembly (KZ400S),

@®Mount the handlebar in its clamps so that the angle of
the handlebar matches the angle of the front fork as
shown in Fig. 344. Torque for the handlebar clamp
bolt is 1.66~2.2 kg-m (11.5~ 16 ft-lbs). Each bolt has
a lock washer.

S40

®Position the engine stop switch housing in place with
its projection in the hole in the handlebar, and tighten
its screws,

eWith the brake lever mounted at the proper angle,
tighten first the upper and then the lower master
cylinder clamp bolt to 0.6~0.9 kg-m (52~ 78 in-lbs)
of torque (KZ400D),

eWith the brake lever mounted at the proper angle,
tighten the brake lever bolt (KZ400S),

@Replace the light switch,

eStrap both the light switch wiring harness and the
engine stop switch wiring harness back onto the
handlebar,

@Replace the rear view mirrors.

@Fit the tip of the clutch cable back into the clutch lever,
@Adjust the clutch (Pg. 11).

BRAKE CABLE (Only on KZ400S)
Removal:

http://www.kz400.com

®Loosen the lock nut on the front brake lever, and line
up the slots on the brake lever, lock nut, and adjuster,

Line Uniti slots \
@Remove the cotter pin from the threaded brake cable
extension, screw off the adjusting nut, and free the
brake cable from the brake panel. Also remove the
brake cable joint

@Free the brake cable from the brake lever and the
motorcycle.

Installtion:

@Run the brake cable between the headlight housing
and the right shock absorber. Route the cable with a
minimum of bending so that the inner cable will slide
smoothly,

@Connect the upper end of the cable back into the brake
lever and through the slots on the brake lever, lock
nut, and adjuster.

e@With the brake cable running above the fender stay,
put the brake cable, brake cable joint, and adjusting
nut back onto the front brake panel. Use a new cotter
pin at the end of the threaded brake cable extension,

¢ j WW Brake Cable WAN / | 347)

DISASSEMBLY 89

@Adjust the front brake (Pg. 17).

CLUTCH CABLE
Removal:

@lake out the shift pedal bolt, and remove the shift
pedal.

@eRemove the left foot peg bolt, left foot peg, and side
Stand spring.

@eRemove the engine sprocket cover screws (+1), and
pull the cover out of place.

@Remove the cotter pin from the clutch release lever,
and free the clutch inner cable tip from the lever and
the engine sprocket cover,

Inner Cable Tip

Clutch Release Lever 348)

eUnfasten the straps (2) that hold the clutch cable to
the down tube, slip out the cable, and refasten the
straps.

@Loosen the lock nut on the clutch lever, and screw
in the adjuster.

®line up the slots in the clutch lever, lock nut, and
adjuster, and free the inner cavle from the lever,

@Pull the cable free from the motorcycle,

90 DISASSEMBLY

Installation:

®Run the upper end of the cable between the left front
shock absorber and the head pipe to the clutch lever.

eFit the tip of the cable back into the clutch lever.

@Run the lower end of the clutch cable between the left
down tube and the lower part of the engine into the
engine sprocket cover and spring, and fit the tip of the
inner cable into the clutch release lever,

eUsing a new cotter pin, secure the cable tip to the
release lever.

@Replace the engine sprocket cover using the shift shaft
oil seal guide (special tool) to protect the oil seal in
the cover, and tighten its screws,

@fFil the side stand spring into place, and then secure
the left foot peg with its bolt,

@Replace the shift pedal so that its end matches the
level of the dynamo cover lower right screw.

®Secure the cable to the left down tube with the straps
(2).
@Adjust the clutch (Pg, 11).

THROTTLE CABLES

Removal:

eUnlock the seat, and lift it up.

®lurn the fuel tap lever to the STOP position, slide
back the hose clamps, and pull the fuel hoses (2) off
the tap.

®Unhook the retaining band, and pull the tank off
towards the rear.

eScrew in fully the lock nuts and adjusting nuts at the
upper end of the throttle cables so as to give the
throttle grip plenty of play.

@®Screw one of the cable adjusters out of its bracket,
slip the tip of its inner cable out of the pulley, and
then do the same with the other throttle cable.

|

CableyAdjusters

http://www.kz400.com

®Slide the cables out of the straps which secures them
to the top tube.

®Kemove the engine stop switch housing screws (2), and
open up the housing,

eUnscrew the adjusting nut for the decelerator throttle
cable (the cable next to the starter button), slide it out
of the way, and unscrew the decelerator throttle cable
guide from the engine stop switch housing.

@Slip the decelerator throttle cable tip from its catch
in the throttle grip, and pull the cable out of the engine
stop switch housing and free from the motorcycle.

Decelerator Cable Tip)

@Unscrew the accelerator throttle cable guide from the
engine stop switch housing, slip the cable tip out of
its catch in the throttle grip, and pull the cable from
the engine stop switch and free from the motorcycle,

Installation:

®Screw the accelerator throttle cable guide (shorter than
the decelerator throttle cable guide) into the front
engine stop switch hole. Screw it in most of the
way, and then lightly tighten the guide nut,

http://www.kz400.com

eScrew in the decelerator cable guide most of the way,
and then lightly tighten the guide nut.

®lurn the throttle grip so that the cable catches are
facing up, and fit the accelerator throttle cable tip
into the front hole and the decelerator cable tip into
the rear hole.

ePut the engine stop switch housing together and
tighten its screws. The upper half of the housing has a
small projection which fits into a hole in the handlebar,

eScrew the adjusting nut back onto the decelerator
throttle cable guide,

@®Run both cables between the right front shock absorber
and the head pipe, through its straps on the top tube
with the accelerator throttle cable above the other cable
to the carburetors, The cables should be naturely rout-
ed, neither one twisted about the other.

®@]urn each guide in the direction of its cable, and tighten
its guide nut to secure its guide in the proper position.

efit the tip of the accelerator throttle cable into the
rear catch in the pulley, and screw its adjuster down
into the bracket all the way.

Fd =. ae

i. | i % * | ve ’ : " : 7

— ~\ <a >

te rr)

eFit the tip of the decelerator throttle cable into the
other catch, lift the adjuster into its bracket turning
the throttle grip at the same time If necessary, and
screw its adjuster in.

@Center the adjusters in their brackets, and tighten the
lock nuts,

@Replace the fuel tank, and hook jts retaining band,

efit the fuel hoses back onto the fuel tap, and slide
the clamps back into place.

@Push the seat into place.

@Adjust the throttle cables (Pg. 9).

DISASSEMBLY 91

SPEEDOMETER CABLE

Removal:

@Disconnect the upper and lower ends of the speed-
ometer cable.

@Pull the cable free.

Installation:

@Run the cable through its guide, and secure the upper
end of the cable to the speedometer with pliers.

@lnsert the speedometer inner cable into the speedometer
gear housing while turning the wheel so that the slot
in the end of the cable will seat in the tongue of the
speedometer pinion. Tighten the cable nut or the
cable bolt,

TACHOMETER CABLE (Only on KZ400D)
Removal:

@Disconnect the upper and lower ends of the tachometer
cable with pliers.

®Free the cable from the motorcycle.

Installation:

@®Run the tachometer cable through its guide, fit the
inner cable into the tachometer, and tighten the cable
nut with pliers.

eFit the bottom end of the cable into its place in the
cylinder head cover. Turn it if necessary so that it
fits all the way back into place, and tighten its nut
with pliers.

SPEEDOMETER
Removal:

@Disconnect the upper end of the speedometer cable
with pliers.

@Remove the cap nuts (2) from the bottom of the
speedometer holder. Each cap has a lock washer and
flat washer.

@Pull up on the speedometer, and pull out the illuminator
lights (2) from its base to complete speedometer re-
moval,

Installation Note:

@Be sure the cable runs through its guide at the 3-way
joint,

TACHOMETER (Only on KZ400D)
Removal:

@Disconnect the upper end of the tachometer cable
with pliers.

eRemove the cap nuts (2) from the bottom of the
tachometer holder, Each cap nut has a lock washer
and flat washer.

ePull up on the tachometer, and pull out the illuminator
lights (2) and indicator lights (2).

Installation Note:

®lhe proper connections in the base of the tachometer
are as follows: black/yellow and blue to tachometer
illuminator light sockets (2), black/red and black/ yellow
to high beam indicator light socket, and brown and
green/white to brake light failure indicator light
sockeL,

92 DISASSEMBLY
HEADLIGHT UNIT

Headlight Unit
(US model)

N= ©

. Headlight Unit

Rim

. Mounting Screws

Adjust Screw
Spring

Washer

Sealed Beam Unit

. Washers

Nuts

. Nut

. 9ocket
. Headlight Housing

(European model)

http://www.kz400.com

. Nuts

. Collar

. Washer

. Housing Mounting Bolts
. Collar

. Lock Washer

. Retaining Screws
. opring

. Reflector

. Headlight Bulb
. City Light Bulb

Socket

Removal:

@Take out the retaining screws (3) (2), pull the bottom
of the headlight unit @) out of its housing 42, and
then push down on the top of the headlight rim @
to free the unit from the housing.

eDisconnect the headlight socket 1) from the rear of
the unit (US model).

eDisconnect the headlight socket (1) and the city light
24 from the rear of the unit (European model).

®Remove the mounting screws (3), nuts @), washers
(8) (2 ea), and the beam horizontal adjust screw @.
A nut (0, washer @), and spring (5) come off with
the adjust screw.

Installation Notes:

1. The washer on the adjust screw goes between the
spring and the bracket,

2. The top of the sealed beam unit is marked TOP.

3. Carry out the horizontal beam adjustment after
installation (Pg. 22 ),

INDICATOR LIGHTS (turn, neutral and oil)
Removal:

@Remove the nut from the ignition switch, and take
off the ignition switch upper cover,

@Remove the indicator lights (3).

Installation Note:
@Use 12V 3.4W bulbs for indicator light replacement.

IGNITION SWITCH

Removal:

@Take out the retaining screws (2), pull the bottom of
the headlight unit out of its housing, and then push
down on the top of the headlight rim to free the unit
from the housing.

@Disconnect the headlight socket from the rear of the
unit (US model),

Disconnect the headlight socket and the city light from
the rear of the unit (European model),

eRemove the headlight housing mounting bolts (2).
Each bolt has a nut and washer,

@Remove the headlight housing.

@Remove the nut from the ignition switch, and take
off the ignition switch upper cover,

®Disconnect the ignition switch wiring harness socket
from the plug it connects to in the headlight housing,
and push the socket out of the housing.

@Remove the ignition switch lower cover screws (2),
and remove the ignition switch lower cover, ignition
switch fitting, and ignition switch,

http://www.kz400.com

Installation:

efit the ignition switch, switch fitting, and lower cover
in place, and screw in both lower cover screws. Each
screw has a lock washer,

@®Reconnect the ignition switch wiring harness socket
to tts plug In the headlight housing,

®Fit the ignition switch upper cover in place, and tighten
its mul,

@Mount the headlight housing in place tightening its
mounting bolts, The sequence is mounting bolt, flat
washer, fork cover, housing insert, and nut,

®Connect the headlight plug to the headlight, fit the
headlight into the housing, and tighten its retainine
screws, Each screw has a lock washer (US model).

*Connect the headlight plug to the headlight, fit the
headlight and city light into the housing and tighten
Ils retaining screws,
(European model).

eAdjust the headlight vertically (Pg. 22).

Each screw has a lock washer

FRONT FORK

Removal (left shock absorber):

#Remove the front wheel (Pg. 72 or 74).

@Remove the bolts (3) that hold the front fender to
the left shock absorber,

@Remove the caliper mounting bolts (2), and rest the

caliper on some kind of stand so that the pipe does
not get bent (KZ400D),

' Mounting Bolts

—

®|f the shock absorber is to be disassembled after re-
moval, loosen the shock absorber top bolt,

DISASSEMBLY 93

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eWith a twisting motion, work the shock absorber down
and oul,

Installation (left shock absorber):

eSlide the shock absorber up through the lower and
upper clamps until the upper surface otf the tube ts
even with the upper surface of the stem head. Tighten
the upper clamp bolts with 1.6~2.2 kg-m (11.5~16
ft-lbs) of torque and the lower clamp bolts with 2.0
~ 3.0 ke-m (14.5 ~ 22 ft-lbs),

@if the top bolt was loosened during removal, Ughten
it with 2.5™~ 3.0 keem (18 ~ 22 ft-lbs) of torque.

#Mount the caliper to the shock absorber tightening the
bolts with 2.5 ~ 3.3 kg-m (19 ~ 23 ft-lbs) of torque.
Each mounting bolt has a flat washer and lock washer
(KZ400D).

@/nstall the fender bolts,
each bolt,

eMount the front wheel (Pg.72 or 74).

There is a lock washer for

Removal (right shock absorber) :

@®Remove the front wheel (Pg. 72 or 74).

@eRemove the bolts (3) that hold the front fender to
the right shock absorber.

®lf the shock absorber is to be disassembled after
removal, loosen the shock absorber top bolt,
®Loosen the upper and lower clamp bolts.

eWith a twisting motion, work the shock absorber down
and out,

Installation (right shock absorber):

@Slide the shock absorber up through the lower and
upper clamps until the upper surface of the tube is
even with the upper surface of the stem head. Tighten

94 DISASSEMBLY

Front Fork

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. lop Bolt

. O Ring

. Upper Clamp Bolt

. Lock Washer

. Stem Head Clamp Bolt
. Stem Head

. Nut

. Ring Cap

Left Fork Cover
Inner Race

. Stem Base Cover
. Damper Ring

. Damper

. Steering Stem

. Lower Clamp Bolt
. Lock Washer

. Spring

. Inner Tube

. Right Fork Cover
. Right Outer Tube
. Bolt

. Gasket

. Dust Seal

. Clip

. Oil Seal

. Piston Ring

. Spring

. Cylinder

. Left Outer Tube
. Gasket

. Allen Bolt

. Axle Clamp
. Stud Bolt

. Nut

. Cylinder Base

36, Lock Washer

the upper clamp bolts with 1.6~2.2 kg-m (11.5~16
ft-lbs) of torque and the lower clamp bolts with 2.0
~3.0 kg-m (14.5~22 ft-lbs).
elif the top bolt was loosened during removal, tighten
it with 2.5 ~ 3.0 kg-m (18 ~ 22 ft-lbs) of torque.
@Install the fender bolts. There is a lock washer for
each bolt,
®Mount the front wheel (Pg. 72 or 74).
Disassembly:
@Remove the top bolt (1), and pull out the spring 17).
ePour the oil into a suitable container, pumping as
necessary to empty out all the oil.
@Slide the dust seal 23 off the inner tube 18 .
®Keeping the cylinder and piston unit 28 from turning
by use of the front fork cylinder holder and holder
adapter (special tools), unscrew the Allen bolt 3) from
the bottom of the outer tube 29), and then separate
the inner tube from the outer tube by pulling it out.

Allen Wrench

eSlide or push the cylinder and piston unit and its spring
4? out the top of the inner tube,

@Remove the clip 24 from the outer tube, and then
pull out the oil seal 25) .

eRemove the cylinder base 3 out the top of the outer
tube,

Assembly:

e@Place the cylinder base into the outer tube,

eReplacing the oil seal with a new one, apply oil to the
outside, and fit it in with the front fork oil seal driver
(special Lool),

= il
JFork}Oil Seal Driver
57001-1911

@Replace the clip.

@Replace the cylinder and piston unit together with its
spring into the inner tube, pushing it all the way down
so that the cylinder projects out the bottom,

efit the bottom of the cylinder into the cylinder base,
and then push the inner tube fully into the outer tube.

DISASSEMBLY 95

@Apply a non-permanent locking agent to the Allen bolt,
and tighten it in place.

@Slide the dust seal into place.

®Refill with 160 cc of fresh SAE 5W20 oil.

®|nsert the spring with the concentrated portion up.

@Replace the top bolt.

STEERING STEM

Removal:

eUncap the bleed valve on the caliper, connect one end
of a clear plastic hose to the valve, and run the other

end of the hose into a container (KZ400D),

@Open the bleed valve, and pump the brake lever until
all the fluid is drained (KZ400D),

®Remove the plastic hose, close the bleed valve, and
replace the cap (KZ400D).

@Remove the front wheel (Pg. 72 or 74).

@Remove the clamp bolts (2) which secure the master
cylinder to the handiebar, remove the banjo bolt that
connects the upper brake hose to the 3-way joint, and
then remove the master cylinder together with the
upper brake hose. The banjo bolt has a flat washer
on each side of the upper brake hose fitting. Wipe
up immediately any brake fluid that spills (KZ400D),

@Remove the caliper mounting bolts (2) and the lower
brake hose banjo bolt, and remove the caliper together
with the lower brake hose by pulling the lower brake
hose fitting through the fender rubber mount, The
banjo bolt has a flat washer on each side of the lower
brake hose fitting. Wipe up immediately any brake
fluid that spills (KZ400D),

@Remove the fender bolts (6), and take off the fender.

@Loosen the upper and lower clamp bolts on both sides,
and remove each shock absorber by working it down
and out,

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(Upper/Clamp

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96 DISASSEMBLY

@Remove the tachometer cable guide bolt, and dis-
connect the tachometer cable at the tachometer.
@Disconnect the front brake light switch leads from the

switch (KZ400D),
@Remove the 3-way joint (KZ400D),

@Take out the retaining screws (2), pull the bottom of

the headlight unit out of its housing, and then push
down on the headlight rim to free the unit from the
housing,

e@Disconnect the headlight socket from the rear of the
unit (US model),

@Disconnect the headlight socket and city light from
the rear of the unit (European model).

@Disconnect the turn signal leads (gray and black/yellow)
and the main wiring harness plugs.

eRemove the headlight housing mounting bolts (2).
Each bolt has a flat washer and nut.

®Kemove the headlight housing.

@Holding the instrument unit so that it doesn’t fall,
remove the nuts (2) that secure the instrument unit
to the stem head, and then remove the instrument
unit.

7 i
1. Sm x

@Loosen the stem head clamp bolt, stem head bolt,
and stem head flat washers (2).

®@lap lightly on the bottom of the stem head with a
plastic hammer, and remove the fork covers together
with the turn signals, Each fork cover has the ring cap
at the top and the damper, damper ring, and stem base
cover at the bottom.

eContinue tapping up the stem head until it is free of
the steering stem, Let the stem head and handlebar
assembly all hang down out of the way.

e@Pushing up on the stem base, remove the steering stem
lock nut with the stem nut wrench (special tool); then
remove the steering stem and stem base (single unit).
As the stem is removed, some of the steel balls will
drop out of the lower outer race. Remove the rest,

310)

VW mmsteeringistem)Lock Nut

/

fs

@®Remove the steering stem cap and upper inner race,
and remove the upper steel balls (19).

Installation:

@Apply grease to the upper and lower outer races in
the head pipe so that the steel balls will stick in place
during stem insertion, and then replace the upper steel
balls (19) and the lower steel balls (19).

@insert the steering stem into the head pipe, replace
the upper inner race and steering stem cap, and then
tighten the steering stem lock nut, with 2.7~3.3 kg-m
(19.5~24 ft-lbs) of torque.

Note: The steering stem lock nut torque is only pro-

visional. The tightness changes with steering stem

adjustment.

®lap the stem head part of the way into place on the
steering stem,

®Route the main wiring harness directly in front of the
steering stem, and route the light switch wiring harness
and clutch cable in back next to the head pipe.

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\ | eh t swittwirmeinne 7

Fs Ld
4, ’ “4

@Slide the left shock absorber (the one that holds the
caliper) through the left stem base, fork cover, and
stem head so that the upper surface of the tube ts
even with the upper surface of the stem head; tighten
the upper clamp bolt with 1.6 ~ 2.2 kg-m (11.5~16.0
ft-lbs) of torque. The sequence is stem base, damper,
damper ring, base cover, fork cover, ring cap, and stem
head.

®Replace the right shock absorber in the same manner
as the left. TVhe throttle cables run between the shock
absorber and head pipe. The engine stop switch wiring
harness runs in front of both the shock absorber and

head pipe.
| Cables BS

@lap the stem head lightly with a plastic hammer the
rest of the way, and replace the stem head flat washers
(2) (thick washer on top) and bolt. Tighten with 5,5
kg-m (40 ft-lbs) of torque.

®Tighten the stem head clamp bolt with 1.6~2.2 kg-m
(11.5~16.0 ft-lbs) of torque.

®lighten the stem base clamp bolts with 2.0~3,0 kg-m
(19.5 ~ 22 ft-lbs) of torque.

eSecure the instrument unit to the stem head, and
tighten the nuts with washers,

®Replace the 3-way joint. Be sure to include the cable
guide with each bolt (KZ400D),

eConnect the front brake light switch leads onto the
switch, The leads may connect either way (KZ400D),

@Run the plugs, sockets, and wiring into the headlight
housing, and connect the plugs and sockets.

eMount the headlight housing in place tightening its
mounting bolts. The sequence is mounting bolt, flat
washer, fork cover, housing insert, and nut,

eCheck that the brake cable is between the headlight
housing and the right shock absorber (KZ400S).

eConnect the turn signal leads. The Jeft turn signal lead
goes to the green lead, and the right is plugged into
the gray lead. Both turn signal black/yellow leads
go to the same black/yellow plug.

DISASSEMBLY 97

®Connect the headlight plug to the headlight, fit the
headlight into the housing, and tighten its retaining
screws. Each screw has a lock washer (US model).

eConnect the headlight plug to the headlight, fit the
headlight and city light into the housing, and tighten
its retaining screws. Each screw has a lock washer
(European model).

@#Run the tachometer cable through its guide, fit the
inner cable into the tachometer, and tighten the cable
nut with pliers.

@install the front fender tightening its bolts (6). Each
bolt has a lock washer.

@®Run the lower brake hose fitting through the fender
rubber mount, and mount the caliper to the shock
absorber tightening the bolts with 2.5~3.3 kg-m (18.0
~ 24 ft-lbs) of torque. Each bolt has a flat washer
and lock washer (KZ400D),

eConnect the lower brake hose fitting to the 3-way joint
tightening its banjo bolt with 2.5~3.3 kg-m (18~ 24
ft-lbs) of torque. There is a flat washer for each side
of the fitting (KZ400D),

@lnstall the master cylinder to the handlebar with the
small projection on the clamp facing the throttle grip,
Tighten first the upper clamp bolt and then the lower
bolt, both with 0.6 ~0.9 kg-m (52~78 in-Ibs) of torque.
Each clamp bolt has a flat washer (KZ400D).

@Run the upper brake hose fitting to the 3-way joint,
and tighten its banjo bolt with 2.5 ~ 3.3 kgm (18~
24 ft-lbs) of torque. There is a flat washer for each
side of the fitting (KZ400D),

®install the front wheel (Pg. 72 or 74).

@Adjust the steering (Pg. 16 ).

@Adjust the headlight vertically (Pg. 22).

@Refill the brake lines (Pg. 143) (KZ400D).

STEERING STEM BEARING

Removal:

@Remove the steering stem (Pg. 95),

@To remove the outer races pressed into the head pipe,
insert a bar into the head pipe, and hammer evenly
around the circumference of each race to drive it out.

374

98 DISASSEMBLY

®lo remove the lower inner race, which is pressed onto
the steering stem, grip the stem in a vice, and use a
metal rod and hammer as shown in Fig, 375,

Lower Inner Race

Installation:

®Apply oil to the outer races, and drive them into the |!

head pipe using the stem cup driver and the bearing
driver holder (special tools).

376

Bearing Driver Holder
57001-139

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> <

fi am , i =a a
i Stem! . up, Dr met a

57001-138
Y hae i

®Apply oil to the lower inner race, and drive it onto
the steering stem using the stem bearing driver and
adapter (special tools),

Stem Bearing Driver
Se a mm

Stem Bearing Driver Adapter
§7001-294 |

re

Lower Inner’ Ra

@/nstall the steering stem (Pg. 96),

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SWING ARM
Removal:

Put the motorcycle up on its center stand, the jack or
block.

@lTake out the clip from the rear torque link bolt, re-
move the nut and lock washer, and free the torque
link from its bolt,

*Being careful not to bend or otherwise damage it,
free the rear brake light switch spring from the tab
on the brake pedal.

#Remove the adjusting nut from the end of the brake rod,
and then free the rod from the cam lever by depressing
the brake pedal. Remove the brake rod spring and joint,

@lake out the cotter pin, remove the axle nut and
washer, and pull out the axle.

@*Remove the axle sleeve from the right side of the
wheel.

®Posilion the chain on the rear sprocket so that the
drive chain master link is at the rear,

@Remove the clip carefully from the drive chain master
link using pliers, and then remove the master link.

®vurn the rear wheel so thal the rear sprocket will be
free from the chain.

@Remove the coupling sleeve nut and washer,

@Slide the rear wheel together with the sprocket and
coupling free from the motorcycle,

@Remove both chain adjusters.

@Remove the rear shock absorber bolts and lock washers
(2 ea).

@®Remove the pivot shaft nut, and pull out the pivot
shaft,

y / /

ePull the swing arm free from the motorcycle, A cap
on each side of the pivot will drop off.

eTake out the screws (2) to remove the chain guard.

®Remove the clip, nut, lock washer, and bolt to remove
the torque link.

Installation:

®|nsert the end of the torque link into its place in the
swing arm, and replace its bolt, lock washer, nut and
clip. The torque for the nut is 2.6~3.5 kg-m (19~
25 ft-lbs).

@Replace the chain guard, Each screw has a lock washer.

®Replace the caps, one on each end of the pivot, position
the pivot of the swing arm into its place in the frame,
and slide in the pivot shaft from right to left. A screw-
driver inserted into the left side of the pivot will keep
the left cap in place and can be used to alter the
position of the distance collar, if necessary, so that
the pivot shalt will run through the pivot easily.

Swing Arm

|. Pivot Shaft
2, Cap

3. O Ring

4. Sleeve

5. Distance Collar
6, Bush

7, Grease Nipple

$. Swing Arm

9. Nut

10, Adjusting Bolt
1]. Nut

}2, Chain Adjuster

DISASSEMBLY 99

®Replace the pivot shaft and nut; tighten the nut with
6~10 kg-m (43~72 ft-lbs) of torque.

®Replace the rear shock absorber bolts and lock washer,
tightening each bolt with 2.6 ~ 3.5 kg-m (19 ~ 25
ft-lbs) of torque.

100 DISASSEMBLY

@Replace both chain adjusters. The right side of the
right chain adjuster is thicker than the other sides.
eCheck to see that the torque link bolt is in place in
the brake panel, and slip the wheel into place inserting
the coupling sleeve through the left chain adjuster and

left side of the swing arm.
The rest of the steps are the same as those in the
rear sprocket and wheel coupling installation (Pg. 87).

Disassembly:
eUsing a suitable tool pull out the sleeve @ from each

side of the pivot, and then slide out the distance
collar ‘5,

®Use a metal rod and hammer to tap out the bush
‘6 from each side of the pivot.

Assembly Notes:

1. Replace the bushes with new ones if either one has
worn past the service limit (Pg. 153) or has been
removed. Apply oil to the bushes before installing
them with a press,

2. Wipe the old grease off the sleeves, and apply fresh

grease, especially in each sleeve groove.

Groove

REAR SHOCK ABSORBERS

Removal (one side only):

@Remove the chrome bar mounting bolts (2), loosen
the shock absorber cap nuts (2), and take off the
chrome bar,

http://www.kz400.com

eLifting up on the rear wheel as necessary to avoid
damaging the shock absorber bolt threads, remove
the shock absorber bolt.

@®Remove the cap nut, lock washer, and flat washers,
and pull off the shock absorber.

Installation (one side only):

@Fit the shock absorber on its stud.

®Lifting up on the rear wheel, insert the shock absorber
bolt with its lock washer, and tighten with 2.6 ~3.5
kg-m (19~25 ft-lbs) of torque.

@Replace the large flat washer, small flat washer, and
cap nut, and then fit the chrome bar into place between
the flat washers on each side.

Replace and tighten the chrome bar mounting bolts (2).
Each bolt has a lock nut washer and flat washer.

@Tighten each cap nut with 2.6 ~ 3.5 kg-m (19~ 25
ft-lbs) of torque.

Removal (both sides):

@Remove the chrome bar mounting bolts (2).

@Remove the rear shock absorber cap nuts (2), and take
off the chrome bar. Also remove the lock washers
(2) and flat washers (4).

eLifting up on the rear wheel as necessary to avoid
damaging the bolt threads, remove the rear shock
absorber bolts (2).

@Pull each shock absorber off its stud.

Installation (both sides):

®@Fit each shock absorber on its stud.

®Lifting up on the rear wheel, insert each shock absorber
bolt with its lock washer, and tighten with 2.6 ~ 3.5
kg-m (19~25 ft-lbs) of torque.

®@Replace the large flat washer on each stud.

eit the chrome bar in place, and tighten its mounting
bolts (2). Each bolt has a lock washer and flat washer.

®Replace the flat washer, lock washer, and then cap nut
on each side. Tighten the cap nuts with 2.6~3.5 kg-m
(19~25 ft-lbs) of torque.

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MAINTENANCE 101

Maintenance

AIR CLEANER

A properly cared for air cleaner ensures that only
clean, filtered air is supplied through the carburetor into
the engine. If the air is supplied directly without
filtering, not only will dirt and dust from the air plug up
carburetor passages causing the engine to run poorly,
but also the dust that enters the engine will act like
grinding compound wearing down the cylinder, piston,
and rings. If the air cleaner clement is damaged or too
coarse, the result will be the same as though no element
were used.

An air cleaner element clogged with dirt chokes the
air supply to the engine, resulting in an overly rich fuel/
air mixture and inefficient combustion, This in turn
causes overheating from carbon build-up, reducing engine
power,

Cleaning and replacement

The air cleaner element must be cleaned periodically
(Pg. 180).

Remove the air cleaner element (Pg. 27 ), clean it
by swishing it around in a bath of a high flash point
solvent of some kind, and then dry it from the inside
using compressed air. Since this is a dry-type clement,
do nol use Kerosene or any fluid which would leave
the element oily.

NOTE: Because of the danger of highly flammable
liquids, do not use gasoline or low flash point solvents
lo clean the element,

Carburetors

Air Cleaner

1, Air Cleaner Housing 4
2. Air Cleaner Element So oa

3. Air Cleaner Duct 6 5

4. Screw

5. Lock Washer S. Screen

6. Washer 9, Foam Rubber
7. Side Cover 10. Sereen

Since repeated cleaning coarsens the element, replace
it with a mew one every 10,000 km or after it has been
cleaned 5 times, whichever is sooner, Also, if there
is a break in the element material or any other damage
to the element, replace the element with a new one.

Upper Chamber
Linkage Mechanism
Starter Plunger Unit
Choke Lever
Carburetor Tube

6, Float Chamber

7. Drain Plug

6. Carburetor Tube

9. Pulley

IO. Pulley Stop Screw
li. Fuel Hose

12, Balance Adjusting Screw

ee ee
7 = a + .

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102 MAINTENANCE

CARBURETORS

The carburetors perform the function of mixing the
fuel and air in the proportions necessary for good engine
performance al varying speeds and loads. In order for
them to function satisfactorily, they must be kept well
adjusted and maintained. The throttle cable adjustment
(Pg. 9) and the pilot screw, idling, and synchronizing
adjustments (Pg. 10 ) are covered in the Adjustment
Section. The discussion here concerns the fundamentals
of carburetor operation, special adjustments, and the
checking and replacement of carburetor parts,

Carburetor Construction

|. Slow Air Jet 13. Screw

2. Main Air Jet 14. Float Valve Needle
3. Vacuum Plug 15, Float

4, Carburetor Cap 16. Slow Jet

5. Batterfly Valve 17, Pilot Jet

6. Vacuum Piston 18. Main Jet

7, Screw 19, Jet Keeper

8, Jet Needle 20. Pilot Passage Plug
9. Needle Jet 21. Starter Jet

10. Float Valve Seat 22. Spring

11. Float Bowl 23. Pilot Screw

12, Retainer 24, Mounting Plate

A linkage mechanism turns each carburetor butterfly
valve the same amount in response to throttle grip
movement so that the carburetor operation is in unison.
As the throttle grip is turned counterclockwise, the
throttle accelerator cable turns the carburetor pulley,
which through the linkage mechanism opens the butter-
fly valves. As the throttle grip is turned clockwise or
is released, the linkage mechanism return spring together
with the throttle decelerator cable closes the butterfly
valves,

One of the basic principles in carburetor operation
is that the pressure exerted by a moving body of air

is less than atmospheric pressure. As the engine draws
air in through the carburetor bore, the air pressure in
the carburetor bore is less than the air pressure in the
float chamber, which is at atmospheric pressure. This
difference in air pressure forces the fuel up through the
passages into the carburetor bore where it is then atom-
ized by the air, which is flowing at high speed to the
engine.

Another important principle is the Venturi Principle,
which states that when an air passage narrows, moving
air flows faster, exerting even less pressure. For example,
at low speeds (0 ~ 4 throttle) the vacuum piston Is at
its lowest position, forming what ts called the “primary
venturi’. Since the engine intake requires less air at
lower engine speeds, there would not be enough air flow
speed for sufficient fuel to be forced up through the
jets unless the passage (carburetor bore) above the jets
is constricted. The low position of the vacuum piston
constricts this passage so that there will be sufficient
air flaw speed for pressure difference to force the neces-
sary amount of fuel up through the jets.

Thus, the amount of fuel passing through a jet depends
both on the size of the jet (variable in case of the needle
jet) and on the speed of the air flow over the jet. The
speed of this air flow is in turn determined both by the

Venturi Principle

: Vacuum
Primary Secondary

, | Piston
Venturi Movement Venturi

Air Quantity

Air Speed ———

Venturi Area——

SS Engi ne Speed. —___—_——=

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Table 3 Carburetor Specifications

130 (US model)

engine rpm and by the dimensions of the passage (vari-
able by the vacuum piston) just above the jet. The size
of the jet openings, the various dimensions of the air
Passages, and the engine rpm's are correlated through
carburetor design so that, when properly adjusted, the
carburetor meters (measures) the fuel and air in the
correct proportions at different throttle openings.

The carburetor specifications (Table 3 ) have been
chosen for best all around performance, and ordinarily
will NOL require any change. However, sometimes an
alteration may be desirable for improved performance
under special conditions, and when proper mixture is
not obtained after the carburetor has been properly ad-
justed and all parts cleaned and found to be functioning
properly. For example, the quantity of air entering the
carburetor bore is less at high altitude due to the lower
atmospheric pressure. To obtain the proper carburetor
fuel/air mixture, it may be necessary to exchange the
main jet on each carburetor for one a size smaller. In
particularly cold weather, the increased density of the
air may necessitate a size larger main jet for each carbu-
retor,

Since the carburetors regulate and mix fuel and air
going Lo the engine, there are two general types of carbu-
retor trouble: too rich a mixture (too much fuel) and
too lean a mixture (too little fuel). Such trouble can
be caused by dirt, wear, maladjustment, or improper
fuel level in a float chamber, A dirty or damaged air
cleaner can also alter the fuel to air ratio.

Table 4 Mixture Trouble Symptoms

Engine is sluggish Engine overheats

iSmoky exhaust Runs better with choke
}Runs less well when warm lever pushed down
Spark plug burned white
Running is unstable

No power

Spark plug fouled black
Runs better without air
cleaner

The following explanation of the functioning and
maintenance of the carburetors covers the four main
systems for fuel regulation and supply: the starter
system, which supplies the necessary rich mixture for
starling the engine; the pilot system, which supplies
fuel at idling and low speeds; the main system, which
supplies fuel at medium and high speeds; and the float
system, which maintains the fuel at a constant level in
the float chambers.

Starter System

Fig. 388 shows the starter system, which includes the
starter jet (8), starter pipe (7), starter plunger (6) , and
starter air passage (9).

; oa TAL

MAINTENANCE 103

Butterfly Pilot Fuel
Valve Angle | Screw Level |

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22 a a ee ee iy

|, Plunger Shaft + OF Ce. en

2. Rubber Cap a (ow eae a
3. Cap *et ie,

4. Washer Borns

5. Spring See

6. Plunger

7. Starter Pipe
8. Starter Jet
9. Air Passage

The starter system is used for starting to provide
the exceptionally rich fuel/air ratio that is necessary
to enable easy starting when the engine is cold. When
starting the engine, the throttle is left closed, and the
starter plunger is pulled fully open by pushing down the
choke lever. Since the butterfly valve is closed, a high
intake vacuum (low pressure or suction) is developed at
the engine side of the carburetor bore. The starter plung-
er, when raised, opens up the starter passage and an air
passage so that they connect to the engine side of the
carburetor bore. The intake vacuum from the engine as
it is cranked over draws in air through this air passage and
the fuel from the float chamber through the starter
passage. Fuel metered by the starter jet mixes with a
small amount of air drawn in through air bleed holes in
the starter pipe as it rises in the starter fuel passage. This
small amount of air prepares the fuel for better atom-
ization once it reaches the plunger chamber (the area
just below the raised plunger) where the fuel mixes with
the air drawn in through the air passage. This mixture
is then drawn into the carburetor bore where it, to-
gether with a small amount of mixture supplied by the
pilot system, is drawn into the engine.

In order for the starter system to work properly, the
throttle must be kept closed so that sufficient vacuum
can be built up at the starter outlet. Also, the choke
lever must be pushed down fully so that the starter
plunger will fully open up the air passage and starter

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104 MAINTENANCE

passage to the carburetor bore, Clogged starter jet, starter
pipe air bleed holes will cause insufficient atomization,
thus impairing starter efficiency. Fuel mixture trouble
results if, due to dirt, gum or a defective spring, the
plunger does not seat properly in its rest position after
the choke lever is returned.
Cleaning

Remove the float bowl, and blow the starter pipe,
Starter air passage, the starter jet clean with compressed
air. Do not clean them with wire or any other hard
object which may cause damage.

Remove the starter plunger, and clean it with a high
flash point solvent of some kind.

Pilot System

Fig. 389 shows the pilot system, which includes the
pilot jet(7), slow jet(5), slow air jet(1), pilot passage @),
pilot bypass‘2), pilot screw (9), and pilot outlet(3),

Pilot System

‘+. Pilot Passage
5. Slow Jet
6. Main Jet

|. Slow Air Jet
2. Pilot Bypass
3. Pilot Outlet

7. Pilot Jet
5, Spring
9. Pilot Screw

The pilot system determines the operation of the
carburetor from 0 to % throttle opening, At small
throttle openings, almost no fuel is drawn through the
main system due to insufficient air flow. Instead, the
fuel is drawn through the main, pilot, and slow jets as
a result of the low pressure (suction) brought about by
the demand for air by the engine and the limited but
relatively fast flow of air past the pilot outlet, The
almost closed position of the butterfly valve restricts
the carburetor bore air flow, preventing it from re-
lieving the low pressure created by the engine around

Pilot System Fuel and Air Supply
== Rie Cleaner
[Fuel Tank]

Float Chamber

—— >)5low Air jet

[Stow Jet]
->{Miain Jet}-> [Pilot Jet

——>|Pilot Passage

the pilot outlet while the Venturi effect (the narrower
the air passage, the faster the flow of air) at the engine
side of the butterfly valve further reduces the low
pressure.

The supply of the fuel and air in the pilot system
is shown in Fig. 391. At idling and slightly above, the
fuel passes through the main jet, and is then metered
at the pilot jet and at the slow jet, where the fuel mixes
with air metered by the slow air jet, Then, the fuel
passes through the pilot passage, where the pilot screw
affects the flow, through the pilot outlet into the carbu-
retor bore, and to the engine. As the butterfly valve
turns a little more, the butterfly valve position extends
the low pressure area to the pilot bypass, allowing fuel
to bypass part of the pilot passage to go directly to the
carburetor bore such that the supply of fuel increases
sufficiently with engine need,

Fig. 390 shows throttle opening versus fuel flow for
the main and pilot systems. If trouble occurs in the
pilot system, not only are starting and low speed running
affected, but the transition from pilot lo main system
is not smooth as the throttle is opened, causing a drop
in engine efficiency. Pilot system trouble might be due
to maladjustment; a dirty or loose pilot jet, slow jet, or
slow air jet; or clogging of the main jet, pilot passage,
pilot outlet, or pilot bypass.

Flow Characteristic 390

Gasoline flow cc/min

0 Throttle opening oat

Cleaning and replacement

Wash the main jet, pilot jet, slow jet, and slow air jet
with a high flash point solvent of some kind, and blow
them clean with compressed air, Use compressed air to
clean the pilot passage and slow air jel passage, Do not
use wire for cleaning since any sharp instrument may
cause damage.

Remove the pilot screw, and check that the tapered
portion is not worn or otherwise deformed. If it is,
replace the screw.

[Pilot Screw] —> Pilot Outlet
[Bypass] —>[Carburetor Bore}

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Tapered Portion

‘\. Pilot Screw

Main System

Fig. 393 shows the main system, which consists of
the main jet'5 , needle jet 4 , jet needle 3, vacuum
piston (2), and main air jet'!). Fig. 394 shows the
supply of fuel and air in the main system.

From about % throttle opening, the air flow past the
jet needle outlet is sufficient to cause fuel Lo be drawn
through the main system. The fuel passes through the
main jet and then part of it goes through the pilot and
slow jets as in the pilot system while the rest of it passes
straight up through the space in the needle jet not black-
ed by the jet needle and into the carburetor bore, where
it is atomized by the air flow to the engine.

Main System

|. Main Air Jet
2. Vacuum Piston
3. Jet Needle

4, Needle Jet

5. Main Jet

Main System Fuel and Air Supply

|| Fuel Tank-

Float Chamber

>{ AirCleaner]|—>[Main Air Jet]—>[Needle Jet ]}—>[Needle }

:
[Carburetor Bore

The needle jet has holes to admit the air metered by
the main air jet. This air mixes with the fuel in the
needle jet to prepare the fuel for better atomization
in the carburetor bore,

The lower part of the jet needle is tapered and extends
down into the needle jet. It is fixed to the vacuum
piston, and thus rises up in the needle jet as the vacuum
piston rises. From the time the vacuum piston starts
rising, from about % throttle, until it reaches most of
the way up in the carburetor bore, the fuel is metered
primarily by the jet needle taper. As the jet needle rises,
the needle to jet clearance increases, thereby increasing
the amount of fuel that can pass up through the jet.

The vacuum piston rises only between ‘4 and %4
throttle. Through the hole in the bottom of the piston,
the air pressure in the chamber above the vacuum piston
is reduced by engine intake. Through another hole, the
pressure of the incoming fuel/air mixture is transmitted
to the piston, As engine speed increases, the air pressure
in the upper chamber decreases, and the difference be-
tween the incoming fuel/air mixture pressure and the
upper chamber air pressure will overcome the force of
the weight of the piston, raising the piston to the extent
corresponding to the pressure difference.

As shown in Fig. 387 the quantity of air drawn in
by the engine intake is in direct proportion to engine
rpm, and the speed of the air flow is constant while
the vacuum piston rises from % to %4 throttle. Were
the size of the air passage above the needle jet to change
simultaneously with throttle movement rather than with
engine intake (demand), the speed of the air flow in the
air passage might even drop during a rapid increase in
throttle due to the Venturi effect, causing a slight stall
in acceleration, However, the vacuum piston-butterfly
valve arrangement controls both the air and fuel supply
at sudden throttle for smooth and immediate engine
response.

At % throttle the vacuum piston reaches its highest
position, forming the “secondary venturi” to permil
maximum engine output. At near full throttle openings,
the cross-sectional area of the needle to jet clearance
becomes greater than the cross-sectional area of the
main jet. At these openings, the fuel drawn up into the
carburetor bore is limited by the size of the main jet
rather than the needle to jet clearance.

Trouble in the main system is usually indicated by
poor running or lack of power at high speeds, A dirty
or clogged main jet will cause the mixture to become
too lean. An overly rich mixture could be caused by
clogging of the main air jet, its air passage, or the air
holes in the needle jet; by needle jet or needle wear
(increasing clearance); by a loose main jet; or by a loose
needle jet,

}-—> Engine

MAINTENANCE 105

106 MAINTENANCE

Cleaning and adjustment

Disassemble the carburetor, and wash the vacuum
piston, main jet, needle jet, jet needle, main air jet, and
air passage with a high flash point solvent of some kind,
blowing them clean with compressed air. Do not use
wire for cleaning since a sharp instrument may cause
damage.

If the engine still exhibits symptoms of overly rich
or lean carburetion after all maintenance and adjustments
are correctly performed, the main jet may be replaced
with a smaller or larger one. A smaller numbered jet
gives a leaner mixture and a larger numbered jet a richer
mixture, Many jets are available, bul it is recommended
thal any change be limited to one jet size (10) difference
from the standard jet,

Float System

Fig. 395 shows the float system, which consists of the
float 4 , float valve needle 3 , and float valve seat 1 ,

The float system serves to keep a more or less fixed
level of fuel in the carburetor float chamber at all times
so that the fuel mixture to the engine will be stable.
If the fuel level in the float chamber is set too low,
it will be more difficult for fuel to be drawn up into
the carburetor bore, resulling in too lean a mixture,
If the level is set loo high, the fuel can be drawn up
loo easily, resulling in too rich @ mixture,

The fuel level is defined as the vertical distance from
the center of the carburetor bore to the surface of the
fuel in the float chamber, The fucl level is maintained
al a constant value by the action of the float valve,
which opens and closes according to the fuel level.

6

Float System

|. Float Valve Seat

2, Float Pin

3. Float Valve Needle
4. Float

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As fuel flows through the float valve into the chamber,
the fuel level rises, The float, rising with the fuel level,
pushes up on the needle. When the fuel reaches a
certain level, the needle is pushed completely into the
valve seat, which closes the valve so that no more fuel
may enter the chamber, As the fuel is drawn up out of
the float chamber, the fuel level drops, lowering the
float. The needle no longer blocks the float valve, and
fuel once again flows through the float valve into the
chamber.

Fuel level measurement and adjustment

Turn the fuel tap off, and remove the drain plug
from the bottom of the float bowl. Install the fuel
level gauge (special tool), Hold the plastic tube against
the carburetor body, and turn on the fuel tap. The fuel
level in the plastic tube should come up to 2~ 4 mm
below the edge of the carburetor body,

|. Float Bowl
2, Fuel Level Gauge

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lf the fuel level is incorrect, remove the float bowl
and float. Bend the tang on the float a very slight
amount to change the fuel level. Bending it down closes
the valve sooner and lowers the fuel level; bending it
up raises the level.

After adjustment, measure the fuel level again, and
readjust if necessary.

Cleaning and replacement

If dirt gets between the needle and seat, the float
valve will not close and fuel will overflow. Overflow
can also result if the needle and seat become overworn,
If the needle sticks closed, no fuel will flow into the
carburetor,

lake off the float bowl and float. Wash the bowl and
float parts in a high flash point solvent of some kind,
Use carburetor cleaner if necessary. Blow out the fuel
overflow pipe with compressed air,

Examine the float, and replace if damaged. If the
needle is worn as shown in the diagram, replace the
needle and seat as a set,

Needle Valve

399

Good Bad

CAMSHAFT

The engine has an overhead camshaft (OHC) at the
top of the cylinder head, The camshaft has four cams,
two for the two inlet valves and two for the two ex-
haust valves. At the center of the camshaft is the cam-
shaft sprocket. The sprocket is marked with arrows,
which are referred to during camshaft installation for
easily and correctly resetting the valve timing.

Engine rotation is transmitted from the crankshaft
to the camshaft by a chain running on a sprocket at the
center of each shaft. As the camshaft rotates, the cams
move against the rocker arms, which open and close the
inlet and exhaust valves at the proper intervals (Fig. 400).

MAINTENANCE 107

Valve Timing

400

Inlet open
26° BIDC

Exhaust close
31.5 ATDC

Inlet close

74° ABDC Exhaust open

68.5° BBDC

However, since the time, amount, and duration that
each valve is opened (valve timing) changes with cam
wear, journal wear, and camshaft runout (bend), the
camshaft should be inspected periodically and whenever
liming trouble is suspected. If the valves do not open —
at the right times or if they do not open the correct
amount or duration, there will be a decrease in com-
bustion efficiency, dropping engine power and leading
lo serious engine trouble,

Cam wear

Remove the camshaft, and measure the height of each
cam with a micrometer, If the cams are worn down
past the service limit, replace the camshaft.

Cam Wear Measurement

Cam Height

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108 MAINTENANCE

Table5 Cam Height
Standard

Journal wear

The journal wear is measured using a plastigauge
(press gauge), which is inserted into the clearance to
be measured. The plastigauge indicates the wear by
the amount iL is compressed and widened when the parts
are assembled,

Remove the cylinder head cover, cut strips of plasti-
gauge lo journal width, and place a strip on each journal
parallel to the camshaft and so thal the plastigauge will
be compressed between the journal and the cylinder head
cover, Replace the cylinder head cover, tightening the
stud nuts in the correct sequence with the correct amount
of torque (Pg, 35).

Remove the cylinder head cover, and measure the
plastigauge width to determine the clearance between
each journal and the cylinder head cover. If a clearance
exceeds the service limit, replace the camshaft.

Table 6 Camshaft Journal/Cylinder Head Cover
Clearance

[Standard ‘| __ Service Limi
0.043~0,101 mm | O19 mm

Measure the diameter of each camshaft journal with
a micrometer, If a diameter is less than the service
limit, replace the camshaft.

403

f

*Table 7 Camshaft Journal Diameter

27.94~ 27.96 mm

Service Limit

~ 27,.92mm

Loic!977 kz400 D4 fohan@chub-internet fr

Camshaft runout

Remove the camshaft, and take the sprocket off the
shaft. Set the shaft in V blocks at the journals as shown
in the figure. Measure the runout with a dial gauge set
lo where the sprocket is mounted on the shaft. If the
runout exceeds the service limit, replace the camshaft.

Table 8 Camshaft Runout
Standard Service Limit

under 0.02 mm

CAMSHAFT CHAIN, CHAIN GUIDES

The camshaft chain, which is driven by the crankshaft
sprocket, drives the camshaft at one half of the crank-
shaft rpm. For maximum durability, it is an endless-type
chain with no master link.

Camshaft chain, sprocket, and chain guide wear cause
noise, accelerate wear, and could possibly lead to serious
damage to the engine. If the chain tension can no
longer be adjusted by the chain tensioner, either the
camshaft chain or the chain guides must be replaced.

Camshaft chain wear

Remove the camshaft chain, hold the chain taut with
a force of about 5 kg in some manner such as the one
shown in Fig. 405, and measure a 20-link length. Since
the chain may wear unevenly, take measurements at
several places. If any measurement exceeds the service
limit, replace the chain.

Measure a 20-link length.

Table 9 Camshaft Chain Wear
Standard

. Service Limit

160mm

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Chain guide wear
Remove the chain guides, and inspect them visually.
Replace if the rubber or any other portion is damaged.
Measure the thickness with a ruler. Replace if the
wear has exceeded the service limit.
406

Chain Guides

Table 10 Chain Guide Wear

se! Standard Setvice Limit
4.5 mm

ROCKER ARMS, SHAFTS

There are four rocker arms and shafts tn the cylinder
head cover. The two arms and shafts to the front control
the two exhaust valves, while the two to the rear control
the two inlet valves. The rocker arms are made of a
special steel alloy for durability, and each arm surface
which makes contact with the cam and the valve stem
has been heat-treated to achieve superior surface hard-
ness. An oil hole in each rocker arm enables oj! to
lubricate between the arm and shaft,

Excessive clearance between a rocker arm and shaft
results in engine noise.

Aocker arm wear

Visually inspect where the cam and valve stem wear
on each arm. If there is any damage orf uneven wear,
replace the arm,

Measure the inside diameter of each arm with a
cylinder gauge, If it exceeds the service limit, replace
the arm.

MAINTENANCE 109

Table 11 Rocker Arm Inside Diameter
Standard

| _13.000~13.018mm_ | 13.05 mm

Rocker shaft wear

Measure the diameter of each shaft where the arm
fits. If the diameter is less than the service limit, replace
the shaft.

408

Table 12 Rocker Shaft Dia meter | |

|2.966~ 12.984 mm

CYLINDER HEAD, VALVES

The valves, mounted in the cylinder head, are pushed
open by the rocker arms and closed by the valve springs.

The valve guides and valve seats are pressed into the
cylinder head. The valve seats are cut to the angles
shown in Fig. 409 in order that the seats match the valve
seating surfaces perfectly flush not only to prevent
compression leakage but also to provide efficient heat
transmission.

Cutting Angle of Valve Seat |

Exhaust Inlet

Cylinder Head

The cylinder head is made of aluminum alloy, used
for its high heat conductivity, and is finned on the
outside to aid dissipation of the heat generated in the
combustion chambers. Carbon built up inside the com-
bustion chambers interferes with heat dissipation and
increases the compression ratio, which may result in
preignition, detonation, and overheating. Trouble can
also come from improper head mounting or mounting
torque, causing compression leakage.

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110 MAINTENANCE

Cleaning and inspection

Remove the cylinder head (Pg. 35). Scrape out any
carbon, and wash the head with a high flash point
solvent of some kind,

) ~
ba (@

Lay a straight edge across the lower surface of the
head at several different points, and measure warp by
inserting a thickness gauge between the straight edge
and the head.

If warp exceeds the service limit, replace the cylinder
head,

Table 13. Cylinder Head Warp

Valve, Valve Guide, Valve Seat

Valve face deformation or wear, stem bending or
wear, and valve guide wear are all causes of poor valve
seating. Poor seating can also be caused by the valve
seal itself through heat damage or carbon build-up.
The result of poor seating is compression leakage and
a loss of engine power.

In addition, valve and valve seat wear causes deeper
valve seating and a decrease in valve clearance, Insuf-
ficient clearance upsets valve timing and may eventually
prevent the valve from seating fully. So that the wear
never progresses this far, adjust the valve clearance in
accordance with the periodic maintenance chart (Pg.
180).

Valve inspection

Visually inspect the valve face, and replace the valve
if it shows deformation or uneven wear.

Measure the thickness of the valve head using vernier
calipers, and replace the valve together with its valve
guide if the thickness is under the service limit.

Valve Shape

Ht

Valve Head Thickness

Table 14 Valve Head Thickness

Service Limit
0.75~1.25 mm

0.5 mm

If the seating surface of the valve or the end of the
valve stem is damaged or badly worn, repair the valve
with a valve refacer. The angle of the seating surtace
. La
is45.,

Valve Stem Grinding

413

Valve Refacer

=

I

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CAUTION: If the valve stem is ground down, be sure
to leave at least 4.2 mm of stem end above the wide
groove portion.

Turn the valve in a V block using a dial gauge as
shown to measure the amount that the stem is bent.
Replace the valve if it is bent over the service limit.

amet 15 Valve Stem Bend

| 005mm

Measure the diameter of the valve stem with a micro-
meter, Since the stem wears unevenly, lake measure-
ments at four places up and down the stem, keeping
the micrometer at right angles to the stem.

Replace the valve if the stem is worn to less than
the service limit.

Table 16 Valve Stem Diameter

a tadad —__—_f Servies Limit

Inlet | 6.965 ~ 6,980 mm 6. 90 n mm

6.955 ~ 6.970 mm

Valve guide inspection

Remove the valve, and measure the inside diameter
of the valve guide using a small bore gauge and micro-
meter, Since the guide wears unevenly, measure the
diameter at four places up and down the guide. If any
measurement exceeds the service limit, replace the guide.

MAINTENANCE 111

ca ‘ 3 aa
“aN alve Guide

Service L imit.

7,.000~7.015 mm

If a small bore gauge is not available, inspect the valve
guide wear by measuring the valve to valve guide clear-
ance with the wobble method, as indicated below.

Insert a new valve into the guide and set a dial gauge
against the stem perpendicular to it as close as possible
to the cylinder head mating surface. Move the stem back
and force to measure valve/valve guide clearance. Repeat
the measurement in a direction at a right angle to the
first.

lf the reading exceeds the service limit, replace the
guide.

NOTE: The readling isnot actual valve/valve guide clear-
ance because the measuring point is above the guide.

Table 18

Valve/Valve Gu ide Clearance
(Wobble Method)

TT Stand serie Ent
CTnlet | _0.048~0.120 mm
[Exhaust | _0.065~0.130 mm

Valve seat repair

The valve must seat in the valve seat evenly around
the circumference over a 0,5 ~ 1.0 mm wide area, If
the seat is too wide, the seating pressure per square unit
of area is reduced, possibly resulting in compression
leakage and carbon accumulation on the seating surface.
If the seating area js too narrow, heat conduction from
the valve is reduced, and the valve will overheat-and
warp, Uneven sealing or seal damage will cause com-
pression leakage.

To determine whether or not the valve seat requires
repair, first remove the valve, apply machinist’s dye to
the valve seat, and then use a lapper to tap the valve
lightly into place. Remove the valve, and note where

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112 MAINTENANCE

the dye adheres to the valve seating surface. The distri-
bution of the dye on the seating surface gives an Indi-
cation of seat condition.

Lapper

“sy ,

‘Machinist's

a

NOTE: Jhe valve and valve guide must be in good
condition before this check will give an accurate indi-
cation of valve seat condition,

A valve seat which requires repair is cut with a set
of valve seal cullers, Four cutters are required for
complete repair; one 30° (inlet valve seat only); one
45°: and two 75° cutters, one for the inlet and the
other for the exhaust,

First, cut the seating surface of the valve seat with
the 45° cutter, Cut only the amount necessary to
make a good surface; overcutting will reduce the valve
clearance, possibly making it no longer adjustable,

Next, use the 30° cutter (inlet valve seat only)
to cut the surface inside the seating surface, and then
use the 75° cutter to cut the outermost surface, Cut
these two surfaces so that the seating surface will be
0.5~ 1.0 mm wide.

After cutting, lap the valve to properly match the
valve and valve seat surfaces so that the valve will seat

O

GOOD TOO WIDr.

Valve/Valve Seat Contact Area

well, Start off with coarse lapping compound, and.
finish with fine compound.

Apply compound to the valve seal, and tap the valve
lightly into place while rotating it with a lapper, re-
pealing this until a smooth, matched surface is obtained.

.

420)

be

When lapping is completed and the valves are installed,
check the valve clearance and adjust if necessary (Pg.
14).

Valve Springs

When the valve is not being pushed open by the
rocker arm, valve springs press the valve against the
seat lo prevent compression leakage. An inner spring
and an outer spring are used for each valve to prevent
spring bounce at high speeds. If the springs weaken or
break, compression leakage and valve noise will result,
dropping engine power.

Inspection

Remove the springs, and check the free length of
each spring with vernier calipers. Replace any spring
which is shorter than the service limit.

ey:

TOO NARROW UNEVEN

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Table 19 Valve Spring Free Length

(| Standard | _ Service Limit

32.4 mm

Measure the perpendicularity of each spring by stand-
ing it on a surface plate and settling a square against it,
Replace any spring for which the distance between the
top of the spring and the square is greater than the
service limit.

Valve Spring Perpendiculari !
pring Ferpe ty (2)

|| within 1.5 mm
win t.omm

Table 20 Valve Spring Perpendicularity
pC Standard | Service Limit

Oil Seals

The oil seal around each valve stem prevents oil from
leaking down into the combustion chamber. If an oil
seal is damaged or deteriorated, oil consumption will
increase, carbon may build up in the combustion
chambers, and white smoke may come out of the
exhaust,

If the oil seal appears damaged or deteriorated or
if there is any doubt as to its condition, replace it with
a new one.

CYLINDER BLOCK, PISTONS

The cylinder block is subjected to extremely high
temperatures. Since excessive heat can seriously distort
the shape of a cylinder or cause piston seizure, the
cylinder block is made of aluminum alloy for good heat
conduction and the outside is finned to increase the
heat radiating surface for better cooling efficiency. To
minimize distortion from heat and to maximize dura-
bility, a heat durable, wear resistant sleeve is cold pressed
in each cylinder.

Each piston is made from an aluminum alloy, which
expands and distorts slightly from heat during engine
operation, So that the piston will become cylindrical
after heat expansion, it is designed such that, when cold,

MAINTENANCE 113

it is tapered in towards the head and is elliptical rather
than perfectly round. The piston diameter is made so
that there is enough clearance between the piston and
cylinder to allow for expansion.

Three rings are fitted into grooves near the top of
each piston to prevent compression leakage into the
crankcase and to stop oil from getting up into the
combustion chambers. The top two rings are com-
pression rings, and the bottom ring is an oil ring,

The full floating type of piston pin is used to connect
each piston to its con-rod. The middle part of the piston
pin passes through the small end of the con-rod, and a
snap ring is fitted at each end of the piston pin ina
groove to prevent the pin from coming out. Since the
pin is the full floating type, a small amount of clearance
exists between the piston pin and the piston when the
engine is at normal operating temperatures.

Proper inspection and maintenance of the cylinder
block and the pistons include checking the compression;
removing carbon from the piston heads, piston ring
grooves, and cylinder head exhaust ports; and checking
for wear and proper clearance during top end overhaul,
A worn cylinder, worn piston, or worn or stuck piston
rings cause a loss of compression from gas blowby pass
the rings since the rings will not form a satisfactory seal
between the piston and the cylinder wall during com-
pression, This gas blowby will result in difficult starting,
power loss, excessive fuel consumption, contaminated
engine oil, and possibly engine destruction, Oil leakage
into the combustion chambers causes carbon to build
up on top of the pistons, resulting in preignition, over-
heating, and detonation. A worn piston pin causes
piston slap, which will result in accelerated piston and
cylinder wear,

Engine problems may be caused not only by carbon
deposits and wear or damage to the engine itself, but
also by poor quality fuel or oil, improper oil, improper
fuel/air mixture, improper supply of oil, or incorrect
ignition timing, Whenever Knocking, pinging, piston
slap, or other abnormal engine noise is heard, the
cause should be determined as soon as possible, Neglect
of proper maintenance will result in reduced engine
power and may lead to accelerated wear, overheating,
detonation, piston seizure, and engine destruction,

Compression measurement

A compression test is very useful as an aid in deter-
mining the condition of the engine. Low compression
may be due to cylinder wear; worn piston ring grooves;
worn, broken, or sticking piston rings; poor valve seat-
ing; cylinder head leaks; or damage to the engine such
as piston seizure, Too high a compression may be due
to carbon build-up on the piston heads and cylinder
head, Difference in compression between the cylinders
may cause poor running,

Before measuring compression, check that the cylinder
head and cylinder head cover are tightened down with
the correct torque (Pg. 38), and thoroughly warm up
the engine so that engine oil between the pistons and
cylinder walls will help seal compression as it does
during normal running. While the engine is running,
check that there is no gas leakage from around the
cylinder head gasket.

114 MAINTENANCE

Stop the engine, remove the spark plugs, and push
the compression gauge (special tool) firmly into the
spark plug hole for the cylinder in which the com-
pression is to be measured such that there will be no
leakage. Turn the engine over with the throttle fully
open until the compression gauge stops rising; the com-
pression is the highest reading obtainable.

@)

Table 21 Cylinder Compression
Standard : Li
1O~11 kg/em? 7.5 kg/em? (107 psi) and less

(142~ 156 psi)

than | kg/cm? (14 psi) differ-
ence between the cylinders,

Cylinder, piston wear

Since there is a difference in cylinder wear in
different directions, take a side to side and a front to
back measurement al each of the 3 locations (total of
6 measurements) shown in Fig. 425. If any of the
cylinder inside diameter measurements exceeds the
service limit, or if there is a difference of more than
0.05 mm between any two measurements, the cylinder
will have to be bored to oversize and then honed.
However, if the amount of boring necessary would make
the inside diameter greater than 64,98 mm, the cylinder
block must be replaced,

Cylinder Inside Diameter Measurement

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Measure the outside diameter of each piston 5 mm
up from the bottom of the piston at a right angle to
the direction of the piston pin, If the measurement ts
under the service limit, replace the piston,

NOTE: Abnormal wear such as a marked diagonal
pattern across the piston skirt may mean a bent con-rod
or crankshaft,

Table 23 Piston Diameter

| Statidard)

63.94~63,96 mm

Service Limit
63.5 mm

Table 22 applies only to a cylinder that has not
been bored to oversize, and Table 23 applies only to
the standard size piston, In the case of a rebored cylinder
and oversize piston, the service limit for the cylinder is
the diameter that the cylinder was bored to plus 0,1 mm
and the service limit for the piston is the oversize piston
original diameter minus 0.15 mm. If the exact figure
for the rebored diameter is unknown, it can be roughly
determined by measuring the diameter al the base of
the cylinder.

NOTE: Whenever the piston or cylinder block has been
replaced with a new one, the motorcycle must be broken
in the same as with a new machine.

Piston/cylinder clearance

The piston to cylinder clearance is measured when-
ever a piston or the cylinder block is replaced for a new
one, or whenever a cylinder is rebored and an oversize

|

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piston installed. The standard piston to cylinder
clearance must be adhered to whenever the cylinder
block is replaced or a cylinder rebored. However, if
only a piston is replaced, the clearance may exceed the
standard slightly, but it must not be less than the
minimum in order to avoid piston seizure,

The most accurate way to find the piston clearance is
by making separate piston and cylinder diameter meas-
urements and then computing the difference between
the two values, Measure the piston diameter as just
described, and measure the cylinder diameter at the
very bottom of the cylinder,

Table 24 Piston/Cylinder Clearance

Boring, honing
When boring and honing a cylinder, note the

following:

|. Before boring a cylinder, first measure the exact
diameter of the oversize piston, and then, in accord-
ance with the standard clearance given in Table 23,
determine the diameter of the rebore.

2. Cylinder inside diameter must not vary more than
0.01 mm at any point.

3. There are two sizes of oversize pistons available:
0.5 mm and 1.0 mm. Oversize pistons require over-
size rings.

4. Be wary of measurements taken immediately after
boring since the heat affects cylinder diameter.

Piston/cylinder seizure

Remove the cylinder block and pistons to check the
damage. If there is only slight damage, the piston may
be smoothed with #400 emery cloth, and any aluminum
deposits removed from the cylinder with either #400
emery cloth or light honing. However, in most cases,
the cylinder will have to be bored to oversize and honed,
and an oversize piston installed.

Piston cleaning
As carbon on the piston top reduces piston cooling
efficiency, scrape off any accumulated carbon.

MAINTENANCE 115

Clean carbon and dirt out of the piston ring grooves
using a piece of broken piston ring or some other suit-
able tool,

Piston ring, piston ring groove wear

Visually inspect the piston rings and the piston ring
grooves, If the rings are worn unevenly or damaged, they
must be replaced. If the piston ring grooves are worn
unevenly or damaged, the piston must be replaced and
fitted with new rings,

Measure the width of the ring grooves, and measure
the thickness of the rings, If the width of the grooves
exceeds the service limit, replace the piston, Replace
any rings that are worn down to less than the service
limit,

Table 25 Piston Ring Thickness

et eee
1.460~ 1.475 mm
ond ring | 1.475~1.490 mm

[oiring | 2475~2490 mm

— 26 Piston Ring Groove Width

[| Standard
1.50~1.52mm

[2.50~2.52 mm_

Even though both the piston ring grooves and piston
rings may be in tolerance, parts will have to be replaced
if the ring/groove clearance exceeds the service limit.

With the piston rings fitted into place on the piston,
make several clearance measurements around the grooves
using a thickness gauge.

Table 27 Piston Ring/Groove Clearance

a
0.025~0,060 mm | 0.160 mm

| Second ring ea Gee
Oil ring 0.010~0,045 mm | 0.145 mm

Piston ring end gap

Place the piston ring being checked inside the cylinder
using the piston to locate the ring squarely in place, Set
it close to the bottom of the cylinder, where cylinder

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116 MAINTENANCE

wear is low. Measure the gap between the ends of the
ring with a thickness gauge. If the gap is wider than the
service limit, the ring is overworn and must be replaced.

Gi

Thickness Gauge

Piston Ring

Piston, piston pin, connecting rod wear

Measure the diameter of the piston pin with a micro-
meter, and measure the inside diameter of both piston
pin holes in the piston, If the piston pin diameter is

less than the service limit at any point, replace the piston
pin. If either piston pin hole diameter exceeds the
service limit, replace the piston,

Measure the inside diameter of the con-rod small end.
lf the diameter exceeds the service limit, replace the
connecting rod,

Table 30 Piston Pin, Piston Pin Hole, Small End Dia.
Standard
| Piston pin.

Piston pin on ; ~
hole 15.004~ 15.011 mm 15.08 mm

Small end 1.D.]15.003~15.014mm_ | 15.05mm__|

Service Limit |

NOTE: When a new piston or pin is used, also check
that piston to pin clearance is 0.006 ~ 0.013 mm,
and that pin to small end clearance is within 0,003 ~
0.020 mm.

To the Dealer: When possible, match parts from stock
so that a marked pin is assembled with an A piston, and
an unmarked pin with an unmarked piston,

Lole 1077 K 2400 D4 tohangiolub-interral. +

CRANKSHAFT, CONNECTING RODS

The crankshaft is the part that changes the recipro-
cating motion of the pistons into rotating motion, which
is transmitted to the rear wheel when the clutch is
engaged. The connecting rods are the parts that connect
the pistons to the crankshaft, Crankshaft or connecting
rod trouble, such as worn crankshaft journals or a bent
connecting rod, will multiply the stress caused by the
intermittent force on the pistons, and will result in not
only rapid crankshaft bushing wear, but also noise, power
loss, vibration, and a shortened egnine life. A defective
crankshaft or connecting rod should always be detected
at an early stage and then replaced immediately.

The following explanation concerns the most common
crankshaft and connecting rod problems, giving the
procedure for detecting damage and measuring wear
and runout,

Connecting rod bend, twist

Set the crankshaft in a flywheel alignment jig or on
V blocks on a surface plate. Select an arbor of the same
diameter as the piston pin and of optional length, and
insert it through the small end of the connecting rod.

Using a height gauge or dial gauge, measure the
difference in the height of the rod above the surface
plate over a 100 mm length to determine the amount
the connecting rod is bent,

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Using the arrangement shown in Fig. 434, measure
the amount that the arbor varies from being parallel
with the crankshaft over a 100 mm length of the arbor
to determine the amount the connecting rod is twisted.

lf either of these measurements exceeds the service
limit, replace the connecting rod.

Connecting rod bushing/ournal wear
Bushing wear is measured using a plastigauge (press
gauge), which is inserted into the clearance to be

measured. The plastigauge indicates the wear by the
amount it is compressed and widened when the parts
are assembled.

Remove the connecting rods, cut strips of plastigauge
to bushing width, and place a strip on the connecting
rod bushing half on each connecting rod parallel to the
crankshaft and so that the plastigauge will be compressed
between the bushing and the connecting rod journal.
Replace the connecting rods, tightening the nuts with
the specified torque (Pg. 71).

Remove the connecting rod, and measure the plas-
tigauge width to determine the bushing/journal wear.

Table 32 Connecting Rod Bushing/Journal Clearance

Standard [Service umait —
0.041~0.07 mm

If the clearance has gone beyond the service limit,
replace the bushings as follows.

First measure with a micrometer the diameter of the
crankshaft journals on which the connecting rod fit.
Mark each flywheel in accordance with the journal
diameter (Table 33).

NOTE: Any mark already on the flywheel should not
be referred to during servicing.

436

Connecting Rod Journal |

Table 33. Connecting Rod Journal O.D./Connecting

Rod |.D.
| Connecting Rod

No mark. . 984~35,994 mm | 39,000~39.010 mm
|_1__|35.994~36.000 mm | 39.010~39.016 mm |
Table 34 Bushing Thickness

1.485~1 490 mm

1.480~ 1.485 mm
1.475~1.480 mm_]

Color ators _| .

Select the right bushing in accordance with the com-
bination of the connecting rod and crankshaft coding
(Table 1).

Connecting rod side clearance

Measure the side clearance of the connecting rod with
a thickness gauge as shown. Replace the crankshaft and

MAINTENANCE 117

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118 MAINTENANCE

the connecting rod if the clearance exceeds the service
limit.

7 be ; (37)

2 ;

Thickness Gauge

. 1 a | ‘ = =e =
% yy . - # na,

=

Table 35 Connecting Rod Big End Side Clearance

0.15~0,25 mm oa

Crankshaft runout

Service Limit
0.45 mm

Set the crankshaft in a flywheel alignment jig or on
V blocks, and place a dial gauge to the points indicated.
Turn the crankshaft slowly. The maximum difference
in gauige readings is the crankshaft runout,

If the runout exceeds the service limit, replace the
crankshaft.

Table 36 Crankshaft Runout

Standard

_under 0.02mm

Crankshaft bushing/fournal wear

Remove the crankshaft, cut strips of plastigauge to
bushing width, and place a strip on the half of each
bushing parallel to the crankshaft and so that the plas-
tigauge will be compressed between the bushing and the
crankshaft journal. Install the crankshaft, crankshaft
bushing cap, and the lower crankcase half in such a way
that the crankshaft does not turn, tightening the bolts
in the correct sequence with the specified amount of
torque (Pgs. 59, 66).

Remove the crankshaft (making sure that the crank-
shaft does not turn at any time), and measure the plas-
tigauge width to determine the bushing/journal wear.
If either clearance exceeds the service limit, replace all
eight bushing halves,

ie | f che eos r i # j
. SAHIN MI 2IWSE AOe WOE A
: _ : ins «= © i

2 Pa + =F

Table 37 Crankshaft Bushing/Journal Clearance

0.036~0.078 mm

Measure the journals which wear on these bushings.
lf the micrometer reading is less than the service Jimit,
replace the crankshaft.

*Table 38 Crankshaft Journal (Not Con-Rod) Diameter
| 35.96 mm

35.984~36.000 mm

Set the crankshaft back in place on the upper crank-
case half. Replace the crankshaft bushing cap with the
arrow pointing to the front, tightening the bolts in the
a sequence with the correct amount of torque (Pg.
66).

Measure the crankshaft thrust clearance with a thick-
ness gauge as shown. Replace the crankshaft bushing cap
and crankcase halves as a setif the clearance exceeds the
service limit.

NOTES:

1. The reason that the bushing cap and the crankcase
halves must be replaced together as a set, is that
they are machined at the factory in the assembled
state to ensure that the bushing cap will be aligned
perfectly with the crankcase. A new bushing cap will
not fit the old crankcase.

2, Measure the clearance between the crankshaft bushing
cap and the center portion of the crankshaft flywheel,
flowing the steps in Fig, 441,

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A csh hte 4 Weak 12 (i),
| 7

Table 39 Crankshaft Thrust Clearance

0.10~0.20 mm

Oil passage cleaning

There fs an oil passage running between the crankshaft
journals on each side. Use compressed air to remove any
foreign particles or residue that may have accummulated

MAINTENANCE 119

on the crankshaft can reduce this vibration. However,
troublesome vibration remains unless some additional
measure is taken.

Fig.443 shows the internal engine forces when the
centrifugal force of the counterweights is one half the
inertial force of the pistons. The arrows show the
amount and direction of these forces.

As the crankshaft rotates clockwise, |~5 in Fig. 443,
one half of the inertial force of the pistons is negated by
the vertical component of the centrifugal force of the
counterweights. However, the horizontal component of
the centrifugal force of the counterweights (brought
about by having counterweights) ts not negated by any-
thing. The thick arrows indicate the resulting unbalanced
force, which is the main cause of engine vibration.

The balancer mechanism includes two balancing
weights having one half the centrifugal force of the
counterweights, A balancing weight is installed at an
equal distance on both sides of the crankshaft for
rotation by a chain in such a way that the weights
rotate in the direction opposite to the crankshaft
counterweights,

Fig. 442 shows how this mechanism works at one
crankshaft position. The centrifugal force of the balancer
weights exert a pull on the engine to the lower right
as the arrows in the figure show. On the other hand,

in these passages, Balancer Mechanism

Piston

BALANCER MECHANISM
The balancer mechanism basically consists of two
weights, which are chain-driven by the crankshaft. The
following explanation covers how this mechanism reduce
vibration. foes \ f.
The vibration on a 4-stroke, 2-cylinder engine is
generally greater with larger engine displacement. This | = 2
vibration is natural due to the mechanics of a recipro- |
Balancer Weight

caling engine, but the proper addition of counterweights Counterweight Balancer Weight

(43

Vibration Reduction with Crankshaft Counterweights only

—_

dd) (2) (3)

Piston Inertia Force

Cad)
as
CTT}

Piston

Connecting
Rod

Counterweight

Centrifugal Force

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120 MAINTENANCE

the crankshafl counterweights are exerting a pull on
the engine to the upper left. The centrifugal force
due to the two balancer weights equals the unbalanced
force which results when only the crankshaft counter-
weights are installed, but the forces cancel cach other
since the directions of these forces are opposite. With
the forces cancelled, engine vibration is greatly reduced.
At other crankshaft positions as well, these two forces
are equal and opposing such that they cancel each other,
keeping the system always in balance.

The balancer weights, turning at the same rpm as
the crankshaft, are chain-driven by a sprocket which is
part of the crankshaft. The balancer chain is an endless-
type for maximum durability and wears very slowly due
to its ample lubrication. The chain drives the weights
through a sprocket on each side of the mechanism. Each
sprocket has four springs, which are wedged between the
sprocket and the weights to protect the sprocket and
chain from the severe torque during the combustion
stroke, In the center of each spring is a pin, which
prevents damage to the spring from excessive com-
pression,

If balancer mechanism trouble develops, such as ex-
cessive shall or chain wear, not only are the bearings
and crankcase parts affected but the resulting power loss
and engine vibration may adversely affect performance
and overall engine life.

Balancer shaft, holder wear

Measure with a micrometer the diameter of each shaft
where it wears on the holders, and measure with a
cylinder gauge the inside diameter of each holder, Re-
place a shaft which has worn down on either side to
less than the service limit, Replace any holder for which
the inside diameter exceeds the service limit.

ai Phe I, 19.93 mm
| 20,007 ~ 20.028 mm | 20.08 mm

Holder 1.D,

Chain wear

Remove the chain, hold it taut with a force of about
5 kg in some manner such as the one shown in Fig. 445,
and measure a 20-link length. Since the chain may wear
unevenly, take measurements at several places. If any
measurement exceeds the service limit, replace the chain.

Measure a 20-link length.

Table 41 Balancer Chain Length

[160mm

Service Limit

162.4 mm_

When replacing a chain for a new one, inspect all
the sprockets, If either of the balancer mechanism
sprockets is damaged or overly worn, replace it, If the
crankshalt sprocket is damaged or overly worn, replace
the crankshaft,

NOTE: If the crankshaft is replaced, select the right
bushing in accordance with the combination of the
connecting rod and the crankshaft marks (Pg. 71).

Chain guide wear
Visually inspect the rubber part of each chain guide,
If it is worn down or damaged, replace the guide.
Measure the thickness with a ruler, If the wear has
exceeded the service limit, replace the guide,

| 3
h Upper Lower Mis
a

Pe -_ * >
*

Table 42 Chain Guide Thickness |
Standard | Service Limit __|

Lower

NOTE: The designations upper and lower refer to the
relative position of the chain guides when the engine is
right side up.

Spring free length

Measure the free length of each spring with vernier
calipers, Replace any spring which is shorter than the
service limit,

‘//Iwww.kz400.com ,
http://www.kz400.co MAINTENANCE 121

The clutch release mechanism is shown in Fig. 448.
The clutch release outer worm gear is made of nylon
and the inner one of steel. Assembled into the center
of the release inner gear is the clutch adjusting screw,
which pushes on the push rod and steel ball inside the
drive shaft to release the clutch.

Clutch Release Mechanism Ga
| 0) |
way } MD |

Table 43 Spring Free Length
7 Service Limit
9.8~ 10.4 mm

CLUTCH

Fig. 449 shows the construction of the clutch, which
is a wet, multi-plate type with 6 friction plates 3), 5 steel
plates @) , and 6 steel rings 5). The friction plates are
made of cork, used for its high coefficient of friction,
bonded on a steel core, which provides durability and
warp resistance, The clutch housing (2) has a reduction
sprocket on one side and contains springs to absorb
shock from the drive train,

. Lock Nut

. Adjusting Screw
. Washers

. Outer Gear

. Screws

. Inner Gear

. Spring

. Cotter Pin

. Oil Seal

. Push Rod

Clutch fay 1. Clutch Housing Sprocket 449
bar 2. Clutch Housing
3. Friction Plate

/

4, Steel Plate

SUW UU : :
Rl | | 5. Steel Ring
= AN 6. Spring Plate
(92) 1} f | | Sita
so 8 el | An OFORONL) ) 7. Spring
02) UL fo EES BEES) 8. Bolt
= | PANAAARASEEE 9. Washer
£ aE (7) 10. Spring Plate Pusher
ANAS ay 11. Drive Shaft
S 12. Circlip
(9) 13. Shim(s)

14. Steel Ball
15. Thrust Washer

10) 16. Clutch Hub
47) 17. Shock Damper Spring
— 18. Push Rod

19. Pin

20. Circlip

N39 21. Oil Pump Drive Gear
12 22. Rivet
13) 23. Collar
‘15)
al

Wifty

WA

a.

es (GD)

ee

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122 MAINTENANCE

The friction plates are connected to the clutch housing
by tangs on the outer circumference of each plate, and,
since the clutch housing is chain driven directly by a
sprocket on the crankshaft, these plates are always turn-
ing any time the engine isrunning, The steel plates have
a toothed inner circumference, which meshes with the
splines in the clutch hub on the drive shaft so that the
drive shaft and steel plates always turn together. To
improve clutch disengagement, steels rings are inserted
between the friction and steel plates,

One end of each clutch spring forces against its washer
and bolt, which threads into the clutch hub, and the
other end forces against the spring plate. When the
clutch is left engaged, the springs pressing against the
spring plate force the spring plate, friction and steel
plates, stecl rings, and clutch hub tightly together so
that the friction plates will drive the steel plates by
virtue of their mutual friction and thereby transmit the
power to the transmission drive shaft,

When the clutch lever is pulled to release (disengage)
the clutch, the clutch cable turns the clutch release
inner worm gear in towards the clutch. The clutch
adjusting screw, assembled inside the clutch release inner
worm gear, then pushes the push rod, which through
the steel ball and spring plate pusher pushes the spring
plate. Since the spring plate moves the same distance
that the inner worm gear moves and the clutch hub
remains stationary, the springs are compressed and the
spring pressure is taken off the clutch plates, Because
the plates are no longer pressed together, the power
transmission from the crankshaft to the transmission
drive shaft is interrupted. However, as the clutch lever
is released, the clutch springs return the spring plate
and once again force the spring plate, plate assembly,
and clutch hub tightly together.

A clutch that does not properly disengage will cause
shifting difficulty and possible transmission damage.
On the other hand, a slipping clutch will reduce power
transmission efficiency and may overheat and burn out,
A clutch that does not properly disengage may be caused
by:

1. Excessive clutch lever play.

2. Clutch plates that are warped or too rough.

3, Uneven clutch spring tension.

4, Deteriorated engine oil.

5. Engine oil of too high a viscosity,

6. The clutch housing frozen on the drive shaft.

7, A defective clutch release mechanism.

8. Broken or missing steel rings,

9. An unevenly worn clutch hub or housing.

A slipping clutch may be caused by:

1. No clutch lever play.

2. Worn friction plates.

3. Weak clutch springs.

4, The clutch cable not sliding smoothly.

5. A defective clutch release mechanism.

6. An unevenly worn clutch hub or housing.

Clutch noise may be caused by:

1. Excessively worn primary chain and sprockets,

2. Damaged sprocket teeth,

3, Too much clearance between the friction plate tangs
and the clutch housing.

4. Weak or damaged shock absorber spring(s).

Clutch spring tension

Clutch springs that have become weak will not return
to their original length when disassembled from the
clutch. Their condition can thereby be determined by
measuring the free length with vernier calipers.

lf any spring is shorter than the service limit, replace
all the springs as a matched set to ensure even tension
on the clutch plates,

Table 44 Clutch Spring Free Length
| Standard ——|__—Service Limit__|

Friction plate wear, damage

Visually inspect the friction plates to see whether or
not they show any signs of heat seizure or have become
rough or unevenly worn, Measure the thickness of the
plates with vernier calipers.

If any plates show signs of damage, or if they have
worn past the service limit, replace them with new ones.

Friction Plate Measurement

a

Table 45 Friction Plate Thickness

[Standard | _ Service Limit
:

Clutch plate warp

Place each friction plate and each steel plate on a
surface plate, and measure the gap between each clutch
plate and the surface plate. This gap is the amount
of clutch plate warp.

Replace any plates warped over the service limit.

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Table 46 Clutch Plate Warp

under 0.15 mm [030mm
under 0.20 mm_

Steel ring damage

Visually inspect the steel rings. Replace any which
are bent, broken, or otherwise damaged.

Friction plate/clutch housing clearance

Measure the clearance between the tangs on the
friction plates and the fingers of the clutch housing.
If this clearance is excessive, the clutch will be noisy.

lf the clearance exceeds the service limit, replace the
friction plates, Also, replace the clutch housing if it is
unevenly or badly worn where the friction plates wear
against it,

Friction Piate/Clutch Housing Clearance
(453,

Friction Plate
Clu tch Housing

Table 47 Friction Plate/Clutch owes: Clearance

Clutch housing sprocket damage

Inspect the teeth on the clutch sprocket, Any light
damage can be corrected with an oilstone, but the clutch
housing must be replaced if the teeth are badly damaged.
Damaged teeth on the clutch housing sprocket indicate
that the primary chain, by which it is driven, may
also be damaged. At the same time that the clutch
housing sprocket is repaired or replaced, the primary
chain should be inspected, and then replaced if necessary.

0.15~0.40 mm

Clutch housing/drive shaft wear

Measure the diameter of the drive shaft with a
micrometer, and measure the inside diameter of the
clutch housing. Find the difference between the two
readings to determine the clearance. Replace the clutch
housing if the clearance exceeds the service limit,

Table 48 Clutch Housing/Drive Shaft Wear

Service Limit —
0.020~0,.062mm | 0.162mm

Clutch hub damage

Inspect where the teeth on the steel plates wear
against the splines of the clutch hub. If there are notches
worn into the splines, replace the clutch hub,

Clutch release gear wear

Fit the outer and inner clutch release worm gears
together, and push them back and forth in the direction
of the shaft without turning them. If there is excessive
play, replace them both. Also, replace them if either
one is visibly damaged.

Lubrication
Lubricate the clutch release worm gears with grease.

PRIMARY CHAIN

The power transmission from the crankshaft to the
drive shaft is chain-drive, utilizing a Hy-Vo (high
velocity) chain. This Hy-Vo chain is a locker-joint
type with a pin and locker construction. Some of the
special features of the Hy-Vo chain are its capacity to
transmit much power at high speed, its lack of suscep-
ibility to heal seizure due to a construction which
employs rolling rather than sliding friction, quiet oper-
ation even at high rpm, and low power loss,

Wear

A primary chain which has worn such that it is 1.4%
or more longer than when new is no longer safe for use
and should be replaced. Inspect the wear by measuring
the chain slack, and replace the chain if it has worn
past the service limit. The replacement chain must be
the Tsubakimoto Hy-Vo 3/8P-5/8W, 74-link chain.

MAINTENANCE 123

ttp:/Awww.kz400.cc
124 MAINTENANCE http://www.kz400.com

NOTE: When installing new chain guides, apply a non-
permanent locking agent to the chain guide screws, and
replace the chain guides.

TRANSMISSION

The transmission is a 5-speed, constant mesh, return
shift type. Its cross section is shown in Fig, 457, and
the external shift mechanism is shown in Fig. 465. For
simplicity, the drive shaft gears in the following ex-
planation are referred to as “D” (e.g., Dl=drive shaft
Ist gear) and the output shaft gears as “O”,

Gears D3, O4, and O5 are all splined to and thus
rotate along with their shaft. During gear changes these
gears are moved sidewise on their shaft by the 3 shift
forks, one for each gear, Gears D4, D5, Ol, O2, and
O3 rotate free of shaft rotation, but cannot move side-
wise. Gears DI and D2 are part of shaft rotation and
are unable to move sidewise.

When a new chain is installed, check the chain guides

ot Ss When the shift pedal 22 is raised or lowered, the
andireplace witinewones (S:necessary. shift shalt @2 turns, a pawl @) on the external shift
mechanism arm (26 catches on one of the shift drum
pins id, and the shift drum (7) turns. As the shift drum
turns, the shift fork guide pins 7) (3), each riding in a
groove in the shift drum, shift the position of one or
another of the shift forks 6 19 20 in accordance with
the winding of the grooves, The shift fork ears then
determine the position of gears D3 1), O4 17, and/or
O58. Refer to Figs.458 to 463 for the gear train for
neutral and each of the 5 gears,

A spring 14 is fitted on the external shift mecha-
nism to keep the shift arm pressed against the shift drum
pins to ensure proper pawl and pin contact. When the
shift pedal is released after shifting, the return spring J,
returns the pawl and shift pedal back to their original

F : f 7 | position, So that the transmission will remain where it
Table 50 Primary Chain Guide Thickness was shifted, another spring, the shift drum positioning

pin spring (4), pushes the shift drum positioning pin
3) into one of six positions on the shift drum operating

Transmission Cross Section 5th

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plate 5). Five of these positions are equally spaced and
correspond to the 5 gears. The other position is halfway
between the position for Ist and 2nd gears and corre-
sponds to the half-stroke shift pedal movement from Ist
or 2nd gear required to shift into neutral,

The return spring pin “5 on the side of the crank-
case passes through a cutout on the shift mechanism,
Each time that the shift pedal is operated, the pin limits
the shift mechanism’s range of movement, stopping the
shift mechanism after the paw! on the shift mechanism
arm has rotated the shift drum the proper amount for
gear change. The return spring pin thus prevents the
drum from being rotated too far.

A neutral indicator light is provided so that the rider
can readily determine whether or not the transmission
is in neutral, The neutral indicator switch, installed in
the crankcase near the starter motor, consists of a spring
loaded pin which comes into contact with a nub on the
side of the shift drum whenever the transmission is in
neutral. When the shift drum has shifted the transmission
into neutral, the neutral indicator switch pin touching
this nub completes the neutral indicator light circuit,
which turns the neutral indicator light on,

MAINTENANCE 125

—-

“a

Transmission or external shift mechanism damage,
causing the transmission to misshift, overshift, and/or
jump out of gear, brings about more damage to the trans-
mission and also overrev damage to the engine itself. An
improperly functioning transmission or external shift
mechanism may be caused by the following:

|. Loose return spring pin

2, Broken or weakened return spring or shift drum
positioning pin spring

3. Broken or weakened shift pawl spring

4. Damaged shift mechanism arm

5. Loose shift drum stopper

6, Bent or worn shift fork(s)

7. Worn shift fork groove on gear D3, O4, and/or O5

8. Worn shift fork guide pin(s)

9. Worn shift drum groove(s)

10, Worn or damaged gear dogs, gear dog holes, and/or
gear dog recesses

11. Improperly functioning clutch or clutch release

12. Improper assembly or missing parts

Transmission noise results from worn or damaged
shafts, gear hubs or teeth, bearings, etc.

http://www.kz400.com

126 MAINTENANCE

Shift Mechanism

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8. Shift Drum Stopper
9. Screw

10. Shift Drum Pin

ll. Shift Drum Pin Plate
12, Lock Washer

(15) 13. Serew

as Id. Spring

15. Return Spring Pin
l6, Return Spring

17, Output 4th Gear
18, Output 5th Gear

16) 19. Shift Fork
20, Shift Fork
l. Drive 3rd Gear 21. Shift Rod
9) 2. Shift Drum Positioning Bolt 22. Shift Shaft
3. Pin 23. Shift Pedal
4. Spring 24, Shift Pedal Bolt
os >. Operating Plate 25. Pawl
18 | 6, Shift Fork 26. Shift Mechanism Arm
I7 7. Shift Drum 27. Shift Fork Guide Pin

External shift mechanism inspection
Inspect the shift pawl spring, shift pawls, and return
spring. Replace any broken or otherwise damaged parts.
Measure the free length of the shift pawl spring. If it
exceeds the service limit, replace it with anew one.

Table 51 Shift Paw! Spring Free Length

Check to see if the return spring pin is loose or not.
If it is loose, remove it and apply a non-permanent
locking agent to the threads. Then screw it back in
tightening its lock nut.

Gear backlash

Split the crankcase. Leaving the transmission in
place, measure the backlash between gears O1 and D1,
O2 and D2, 03 and D3, O4 and D4, and O5 and D5.
To measure the backlash, set a dial gauge against the
teeth of one gear, and move the gear back and forth
while holding the other gear steady. The difference
between the highest and the lowest gauge reading is
the amount of backlash. Replace both gears wherever
the amount of backlash exceeds the service limit.

Table 52 Gear Backlash
Service Limit
0,06~0.23 mm

Shift fork bending

Visually inspect the shift forks, and replace any fork
that is bent, A bent fork could cause difficulty in
shifting or allow the transmission when under power to
jump out of gear,

Shift fork/gear groove wear

Measure the thickness of the ears of each shift fork,
and measure the width of the shift fork groove on gears
D3, O4, and O5, If the thickness of a shift fork ear
is under the service limit, the shift fork must be replaced,
lf a gear shift fork groove ts worn over the service limit,
the gear must be replaced.

Table 53 Shift Fork Thickness

Standard Service Limit

Se SS =

4.9~5,0mm

Table 54 Gear Shift Fork Groove Width
Standard ‘ i

Service Limit —
5.25 mm

5.05~5.15 mm

Shift fork guide pin/shift drum groove wear

Measure the diameter of each shift fork guide pin, and
measure the width of each shifl drum groove, Keplace
any shift fork on which the guide pin has worn past the
service limit. Ifa shift drum groove is worn past the ser-
vice limit, replace the shift drum.

MAINTENANCE 127

Table 55 Shift Fork Guide Pin Diameter —
[| Standard ___|_Service Limit |
"7.985~8,000 mm

Table 56 Shift Drum Groove Width
| §.05~8.20 mm |

Service Limit
8.25 mm

Shift fork guide pin/shift drum groove clearance

Measure the clearance between each shift fork guide
pin and shift drum groove with a thickness gauge.
Replace any shift fork with which the clearance exceeds
the service limit.

Table 57 Shift Fork Guide Pin/Shift Drum Groove

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Clearance
¢ "Service Limit
0.38 mm
O30 mm

Gear dog, gear dog hole, gear dog recess damage

Visually inspect the gear dogs, gear dog holes, and
gear dog recesses. Replace any gears that have damaged
or unevenly or excessively worn dogs, dog holes, or dog
recesses.

Gear/shaft wear

Measure the diameter of each shaft and bush with a
micrometer, and measure the inside diameter of each
gear listed below. Find the difference between the two
readings to figure clearance, and replace any gear where
clearance exceeds the service limit.

Table 58 Gear/Shaft, Gear/Bush Clearance

[| Standard ___| Service Limit
|
For | 0,027~0,061 mm _

Ball bearing wear, damage

Since the ball bearings are made to extremely close
tolerances, the wear must be judged by feel rather
than by measurement.

Clean each bearing in a high tlash point solvent ol
some kind, dry it (do not spin it while it is dry), and oil
it. Spin it by hand to check its condition, If itis noisy,
does nol spin smoothly, or has any rough spots, repiace
iL,

KICKSTARTER

Kickstarter construction is shown in Fig. 469. The
kick gear is connected to the primary sprocket on the
crankshaft through the output shaft Ist gear, drive shaft
Ist gear, clutch housing sprocket, and primary chain.

The kick gear (8) , constructed with a ratchet on
one side, is always meshed with the output shaft Ist
gear and turns freely anytime the output shaft is turning.

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128 MAITNENANCE

Kickstarter

19.113) 12)

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The ratchet gear (9) , mounted on the splined portion
of the kick shaft (3), always turns with the kick shaft
and can be moved sidewise on the shaft. A spring “4d
presses on the ratchet gear in the direction of the kick
gear, but, when the kick pedal (1) Is not being oper-
ated, an arm on the ratchet gear is caught on the stopper
12, which prevents the ratchet gear from meshing with
the ratchet on the kick gear.

When the kick pedal is operated, the ratchet gear arm
is freed from the stopper and the ratchet gear then
meshes with the kick gear ratchet rotating the kick gear,
The gear train of the kickstarter system then cranks the
engine. As the engine starts, the primary sprocket
through the gear train turns the kick gear, But, since
the kick gear rotates in the direction of arrow “A” as
shown in Fig. 469, the kick gear ratchet doesn’t catch
on the ratchet gear.

When the kick pedal is released, the kick shaft is
turned by the return spring returning the kick pedal to
its Original position, At the same time the ratchet gear
arm rides up on the stopper, breaking away from the kick
gear. The kick gear now turns freely without hindrance.

If the kick pedal return spring weakens or breaks, the
kick pedal will not return completely or at all, and the
kick gear and ratchet gear will stay partially meshed,
making noise while the engine is running. Kick mecha-
nism noise may also result when the kick gear, collar, or
kick shaft becomes worn.

lf the ratchet gear or the ratchet on the kick gear is
worn or damaged, the kick gear will slip, and it will not
be possible to kickstart the engine.

Kick gear, shaft wear
Measure the inside diameter of the kick gear, and
replace the gear if the diameter is over the service limit.

|. Kick Pedal
2. Bolt

3, Kick Shaft
4. Circlip

5. Spring Guide

6. Kick Spring

. Kick Shaft Collar
. Kick Gear

. Ratchet Gear

10. Spring

ll. Spring Guide

12. Stopper

13. Stopper Bolts

l4. Washer

So oc J

Visually inspect the ratchet portion of the kick gear.
If there is any kind of damage, replace the kick gear,

Measure the kick shaft diameter at the kick gear, and
replace it if it is under the service limit.

Table 59 Kick Gear Inside Diameter

20,000~ 20,021 mm

Table 60 Kick Shaft Diemete at Sek Gear

19.959~20.000 mm

ENGINE LUBRICATION

The engine lubrication system includes the oil screen,
engine oil pump, oil filter, oil pressure relief valve, and
oil passages. An oil pressure indicator switch is provided
lo warn in case of insufficient oil pressure, and an oil
breather keeps crankcase pressure variations to a mini-
mum, The discussion here concerns,how these parts

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MAINTENANCE 129

Engine Lubrication System

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130 MAINTENANCE

work together, how the oil reaches the various parts of
the engine, and how to check the oil pressure. Details
on the engine oil pump, oil filter, and oil breather are
given in the sections (Pgs. 131 ~132) following engine
lubrication.

since the engine lubrication system is the wet sump
type, there is always a supply of oil at the bottom of
the engine in the crankcase, The oil is drawn through
the wire screen into the oil pump as the pump rotors
rotate, driven by a gear attached to the rear of the clutch
housing. The screen removes any metal particles and
other foreign matter of any size which could otherwise
damage the oil pump. From the pump the oil passes
through the oil filter element for filtration, If the
element is badly clogged slowing the flow of oil through
it, oil bypasses the element through a bypass valve in
the filler, After passing through the filter the oil passes
through the crankcase main oi! passage to where it
branches in four different lubrication routes,

One of these routes is to the crankshaft bearings,
from which the oil then goes to the crankshaft journals
al the con-rod big ends and to the starter motor crank-
shaft sprocket, Oil by the force of crankshaft rotation
reaches the cylinder walls, pistons, and piston pins. The
oil then drops and collects at the bottom of the crank-
case to be used again.

Another route leads to the balancer mechanism shafts,
After shaft lubrication the oil drops and collects at the
bottom of the crankcase for recirculation,

A third route for the ojl is through the oil passage
at each end of the cylinder block up to the top of the
cylinder head. The oil reaches the camshaft journals,
camshaft cams, and valve guides. The oil then drops
through the camshaft chain opening back to the bottom
of the crankcase,

A fourth route for the oil is to the transmission
through a passage existing at one of the drive shaft
bearings. Following lubrication the oil drops back down
to the bottom of the crankcase,

Both the oil pressure indicator switch and the oil
pressure relief valve are important for maintaining a
constant oil pressure, The oil pressure indicator switch,
mounted on the upper part of the crankcase, checks
on the oil pressure of the oil in the main oil passage
and lights the oil pressure warning light if the pressure
falls below a safe value, If the oil pressure is insufficient,
the oil pump Is overworn or malfunctioning or there
is insufficient oil to the pump. On the other hand,
if the oil pressure becomes excessive, such as when the
engine is started (especially in cold weather), the relief
valve reduces the oil pressure, The relief valve opens
whenever a pressure of 5.2 kg/em* (74 psi) presses on
the valve spring,

Oil pressure measurement

Remove the oil pressure indicator switch from the
crankcase, and connect the oil pressure gauge adapter
(special tool) in its place. Fit the indicator switch and
the oil pressure gauge on the adapter, and start the
engine. The standard pressure is more than 1.5 kg/cm?
(21 psi) when the engine is at 4,000 rpm and the engine
oil temperature is at approximately 80°C (176°F).

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If the oil pressure is significantly below the standard
pressure, inspect the engine oil pump (Pg. 131). If the
pump is not at fault, inspect the rest of the lubrication
system.

NOTES: |. Apply a non-permanent locking agent to the
switch threads before installing it back on the crankcase.
2. Warm up the engine before measuring the oil pressure.

Oi! pressure indicator switch inspection

The switch should turn on the warning light when-
ever the ignition switch is on with the engine not
running. If the light does not go on, disconnect the
lead from the switch, and use an ohmmeter to check
for continuity between the switch terminal and the
switch body. A reading of zero ohms indicates that
the switch ts not at fault and the trouble is either
defective wiring or a burned-out indicator bulb, If
the ohmmeter does not read zero ohms, the switch
is defective.

The switch should turn off the warning light when-
ever the engine speed rises above 1,500 rpm. If the
light stays on, slop the engine, disconnect the lead from
the switch, and connect the ohmmeter between the
switch terminal and the engine (chassis ground). The
meter should read zero ohms when the engine is off
and infinity when the engine is running above | 500 rpm.
lf the meter reads zero ohms when the engine is running
above 1,500 rpm, stop the engine and measure the oil
pressure (Pg, 130). If the pressure is near the standard
value, replace the oil pressure indicator switch with anew
one.

NOTE: When installing a new switch, use a non-
permanent locking agent on the switch threads and
tighten it with the specified torque (Pg. 183),

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Relief valve wear

Measure the diameter of the valve piston and the
inside diameter of the valve body. Subtract the valve
piston diameter from the valve body inside diameter
to determine the amount of valve wear, If the clearance
exceeds the service limit, replace the valve piston, If
the piston and the inside wall of the valve body are
scratched, replace the relief valve,

Table 61. Relief Valve Wear
Service Limit
|__0,020~0,103 mm

Relief valve spring tension

Measure the valve spring free length with vernier
calipers, If the length is less than the service limit,
ai the spring.

Table 62 Valve Spring Free Length

Standard Service Limit

Engine Oil Pump

The oil pump, installed in the right side of the lower
crankcase half, is a simple trochoid type with an outer
and an inner rotor, The gear on the pump ts driven in
direct proportion to engine rpm by a gear attached to
the rear of the clutch housing,

If the oil pump becomes worn, it may no longer be
able to supply oil to Jubricate the engine adequately.

Outer rotor/inner rotor clearance

Measure the clearance between the outer rotor and
inner rotor with a thickness gauge. If the clearance
exceeds the service limit, replace the rotors.

MAINTENANCE 131

Outer Rotor,
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Table 63 Outer Rotor/!Inner Rotor Clearance
| Standard —————_s|_Service Limit |
0,025~0.115mm_ | O.2imm__ |

Rotor side wear

Lay a straight edge on the oil pump body, and
measure the clearance between the straight edge and
the rotors with a thickness gauge. If the clearance
exceeds the service limit, replace the rotors,

Table 64 Rotor Side Wear

[Standard
0.03~0.09 mm

Outer rotor/pump body clearance

Measure the clearance between the outer rotor and
the pump body with a thickness gauge. If the clearance
exceeds the service limit, replace either the pump body
or the outer rotor depending on which is excessively
worn. The standard inside diameter for the pump body
and outside diameter for the outer rotor are 40.66 ~
40.69 mm and 40,53 ~ 40.56 mm.

Service Limit
0.15 mm

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132 MAINTENANCE

Table 65 Outer Rotor/Pump Body Clearanc

Service Limit

Oil Filter
The oil filter, located in the lower part of the crank-

case, cleanses the oil from the oil pump by filtration

before the oil is used for lubrication,

As the filler element becomes dirty and clogged,
its filtering effect is impaired. If it becomes so clogged
that it seriously impedes oil flow, a pressure bypass
valve in the center of the oil filter bolt opens so that
sufficient oi! will still reach the parts of the engine
needing lubrication. When the filter becomes clogged
such that the oil pressure difference between the inlet
and outlet for the filter reaches 1.3 ~ 1.7 kg/cm? (18
~ 24 psi), the oil on the inlet side pushing on the valve
spring opens the valve, allowing oil to flow to the main
oil passage bypassing filtration,

Since any metal particles or other foreign matter in
the oil reaching the crankshaft and transmission accel-
erales wear and shortens engine life, the oil filler should
never be neglected,

Oil Filter

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l. Relief Valve
2. Filter Element
3. Bypass Valve
4. Filter Base

5. Spring

6. Filter Bolt

7. O Ring

8. O Ring

Replace the filter element in accordance with the
periodic maintenance chart (Pg. 180) since it quickly
becomes clogged with metal filings from the engine and
transmission breaking in. Subsequently, replace the
element al every other oil change. When the filter
is removed for element replacement, wash the rest of the
filter parts in a high flash point solvent of some kind and
check the condition of the O ring. If the O ring is worn
or deteriorated, replace it to avoid oil leakage.

Oil Breather

The oil breather is located on the top of the cylinder
head cover, The underside of the breather opens to the
crankcase, while the upper part connects through the
breather hose to the air cleaner. Its function is to
minimize crankcase pressure variations caused by crank-
shaft and piston movement and to recycle blowby gas.

Gas blowby is the combustion chamber gas escaping
past the rings into the crankcase. A small amount is
unavoidable, but gas blowby increases as cylinder wall
and piston ring wear progresses. If not efficiently re-
moved, blowby gas will seriously contaminate the engine
oil,

Recycling blowby gas means more efficient com-
bustion, but the oil mist resulting from transmission
gear movement must first be removed. The mixture
of blowby gas and oil mist passes through a maze in
the breather, which separates most of the oil from
the gas. The oil which is separated from the gas returns
to the bottom of the crankcase passing by the tacho-
meter gear and camshaft chain. The gas together with
a little oil is drawn through the breather hose into the
air cleaner case. Here the remaining oi! separates and
passes through a hose to the outside, and the gas is
drawn through the air cleaner element and carburetors
into the engine again for combustion.

FUEL TANK

The fuel tank capacity is 14 liters, 3 liters of which
form the reserve supply. A cap is atlached to the top
of the tank, and a fuel tap to the bottom at one side.
An air vent is provided in the cap so that, when the
lap is turned on, low pressure, which would hinder or
prevent fuel flow to the carburetor, will not develop
in the tank,

Fuel tap construction is shown in Fig. 480. The
fuel tap has three positions: stop, on, and reserve, With
the tap in the stop position, no fuel will flow through the
tap; with the Lap in the on position, fuel flows through
the lap by way of the main pipe until only the reserve
supply is left in the tank; with the tap in the reserve
position, fuel flows through the tap from the bottom of
the tank, The fuel tap contains a strainer and a sediment
cup to filler out dirt and collect water,

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Fuel Tap T) 430

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|. Main Pipe 6. Strainer
2. O Ring 7. Plate
3. Body 8. Wave Washer
4, O Ring 9. Valve Gasket
5. Sediment Cup 10, Lever

Inspection and cleaning

If fuel leaks from the cap or from around the fuel tap,
the cap gasket or tap O ring may be damaged. Visually
inspect these parts, and replace if necessary.

Examine the air vent in the cap to see if it is
obstructed, Use compressed air to clear an obstructed
vent,

Periodically inspect and clean the fuel tap strainer
and the sediment cup, using a high flash point solvent of
some kind and a fine brush on the strainer. If the strainer
is damaged, it must be replaced. If the sediment cup
contains much water or dirt, the fuel tank and the
carburetors may also need to be cleaned.

lo clean out the fuel tank, disconnect the fuel hose,
remove the fuel tap, and flush out the tank with a high
flash point solvent of some kind,

To drain the carburetor float bowls, remove the plug
at the bottom of each carburetor. For thorough clean-
ing, remove and disassemble the carburetors (Pgs. 28
~ 30).

WHEELS

Wheel construction is shown in Figs, 482 and 483.
The following sections, Pgs. 133~ 138, cover the tires,
rim and spokes, axle, grease seals, and wheel bearings.
For the brakes, see Pgs. 140~ 148.

TIRES

The tires are designed to provide good traction and
power transmission during acceleration and braking even
under bad surface conditions when they are inflated to
the correct pressure and not overloaded. The maximum
recommended load in addition to vehicle weight is 140
kg.

If the tires are inflated to too high a pressure, riding
becomes rough, the center portion of the tread wears
quickly, and the tires are easily damaged.

MAINTENANCE 133

If inflation pressure is too low, the shoulder portions
wear quickly, the cord suffers damage, fuel consumption
is high, and handling is poor. In addition, heat builds
up at high speeds, and tire life is greatly shortened.

To ensure safe handling and stability, use only the
recommended standard tires for replacement, inflating
them to the standard pressure. However, for continuous
high speed travel, increase the tire pressure from 0,2~0,4
kg/cm? (3 ~6 psi) in. order to minimize heat buildup.
Also, a certain variation from the standard pressure may
be desired depending on road surface conditions (rain,
ice, rough surface, etc.),

Table 66 _‘Tires, Air Pressure (measured when cold)

| |Air Pressure | Size__| Make, Type |

cl. 3.255-18 Yokohama
= ‘ k ee :

Yokohama
O

Tire wear, damage

Tires must not be used until they are bald, or if they
are cut or otherwise damaged. As the tire tread wears
down, the tire becomes more susceptible to puncture
and failure. 90% of tire failures occur during the last
10% of tire life.

Visually inspect the tire for cracks and cuts, replac-
ing the tire in case of bad damage. Remove any imbed-
ded stones or other foreign particles from the tread.
Swelling or high spots indicate internal damage, requir-
ing tire replacement unless the damage to the fabric ts
very minor,

Measure the depth of the tread with a depth gauge,
and replace the tire if tread depth is less than the service
limit.

|

Depth Gauge

Table 67 Tire Tread Depth

: Service Limit

eobine
Front | 4.4mm [ tmm | imm
Rear [| 6.3mm [| 2mm | 3mm

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134 MAINTENANCE

Front Wheel (KZ400D)

20)

Swot aAuNewun—

(21) (22) (23) (24)

(9) (18)

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. Brake Pipe

. Bolt

. Lock Washer

. Washer

. Caliper

. Left Front Shock Absorber
. Circlip

. Grease Seal

. Circlip

. Cap

. Axle

. Lock Washer
. Nut

. Axle Clamp
. Valve Stem
. Inner Spoke
. Outer Spoke
. Rim

. Tube

. Tire

. Speedometer Gear Housing
. Speedometer Pinion

23, Grease Seal

. Front Hub

. Distance Collar

. Bearing

. Gear Drive

. Speedometer Gear

. Right Front Shock Absorber
. Nipple

http://www.kz400.com MAINTENANCE 135
Front Wheel (K 2400S)

Brake Lining Wear Indicator

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1. Cap 10, Torque Link 19, Rim

2. Grease Seal 11. Torque Link Bolt 20, Spoke

3. Collar 12. Secondary Brake Cam Lever 21. Nipple

4, Grease Seal 13. Connecting Rod 22. Valve Stem

5. Brake Cam Shaft 14. Axle 23. Return Spring
6. Collar 15. Axle Clamp 24, Brake Panel

7. Ball Bearing 16. Primary Brake Cam Lever 25. Balance Weight
8. Brake Shoe 17. Brake Cable

9, Front Hub 18. Tube

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136 MAINTENANCE
Rear Wheel _
Brake Lining Wear Indicator 43)

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1, Collar 11. Axle Sleeve 20, Brake Rod 30, Chain Adjuster
2, Grease Seal 12. Washer 2), Joint 31. Washer
3, Wheel Coupling 13. Axle Nut 22, Camshaft 32, Coupling Sleeve Nut
4, O Ring 14. Cotter Pin 23. Coupling Sleeve 33. Axle
5. Shock Damper Rubber 15. Bolt 24, Bearing 34, Lock Washer
6. Distance Collar lo. Brake Lining Wear 25, Nut 35, Bolt
7. Brake Shoe Indicator 26, Double Washer 36. Washer
8. Rear Hub 17. Gasket 27, Sprocket 37. Rear Shock Absorber
9, Brake Panel 18. Cam Lever 28. Adjusting Bolt
10, Bearing 19. Adjusting Nut 29. Nut
Spoke Force

ees §=Pirection of rolation

RIM, SPOKES

The rim of each wheel is made of steel and is
connected to the hub by the spokes. A rim band
around the outside center of the rim keeps the tube from
coming into direct contact with the rim and the spoke
nipples.

The spokes are connected to the hub at a tangent
and in different directions so that different spokes bear
the brunt of the load during different conditions, With
the spokes doing specialized work, the strength of the
spokes can be used more effectively.

When the motorcycle is at rest (Fig. 485 A), the
spokes above the axle are stretched and tense, while the
spokes below the axle are slightly loose and do not
provide support, During acceleration (B), the spokes
running to the hub in the direction of rotation are
stretched, while during deceleration or braking (C), the
spokes running to the hub opposite to the direction of
rotation are the ones that are stretched. In both cases
B and C, the spokes that are not stretched (omitted from
the diagram) are slightly loose and do not provide
support. A damping action to the shock from the ground
is achieved by flexing of the spokes since they are
arranged in this cross pattern instead of running straight
from the hub to the rim.

Since the spokes must withstand this repeated stress,
it is important to take sufficient care that the spokes
are not allowed to loosen and that they are tightened
evenly, Loose or unevenly tightened spokes cause
the rim to warp, increase the possibility of spoke
breakage, and hasten nipple and spoke metal fatigue.
NOTE: The rim size in Table 68 is outer width by
diameter, both in inches. The “W" means that the rim is
welded, The spoke size is diameter number by length
in millimeters. The two numbers for diameter size mean
that each spoke has two diameters, To make the spoke
more resistant to breakage, the diameter is greater near
the hub,

Spoke breakage

lf any spoke breaks, it should be replaced imme-
diately. A missing spoke places an additional load on
the other spokes, which will eventually cause other
spokes to break,

Periodically check that all the spokes are tightened
evenly since they stretch a certain amount during use,
Standard spoke tightening torque is 0,2 ~ 0,4 kg-m
(17 ~ 35 in-lbs). Over or under tightening may cause
breakage.

Rim runout

Set a dial gauge to the side of the rim, and rotate
the wheel to measure axial runout. The difference
between the highest and lowest dial reading is the
amount of runout,

Table 68 Rim, Spoke Size

MAINTENANCE 137

Set the dial gauge to the inner circumference of the
rim, and rotate the wheel to measure radial runout,
The difference between the highest and lowest dial
reading is the amount of runout,

Table 69 Rim Runout
[| Standard [Service Limit
[Racial [under T mm

A certain amount of rim warp (runout) can be cor-
rected by recentering the rim; that is, loosen some
spokes and tighten others to change the position of
different parts of the rim. If the rim is badly bent,
however, il should be replaced.

AXLE

A bent axle causes vibration, poor handling, and
instability.

To measure axle runout, remove the axle, place it
in V blocks that are 100 mm apart, and set a dial
gauge to the axle at a point halfway between the
blocks. Turn the axle to measure the runout. Ihe
amount of runout is the amount of dial variation.

If runout exceeds the service limit, straighten the
axle or replace it, If the axle cannot be straightened
lo within tolerance, or if runout execeds 0.7 mm,
replace the axle.

http://www.kz400.com

138 MAINTENANCE

Table 70 Axle Runout/100 mm
___|_ Standard
0.05 mm

Service Limit
a mm
2mm

i

GREASE SEALS, WHEEL BEARINGS

A grease seal is installed in either side of the front
hub and in the left side of the rear hub. Each grease
seal except the KZ400S left front seal, is a rubber ring
provided with a steel band around the outer circum-
ference. The inner rib of the grease seal is held against
the axle sleeve by a wire spring band, so that it will
seal in the wheel bearing grease and keep dirt and
moisture from entering the hub. A damaged grease
seal will result in accelerated bearing wear.

The grease seal in the left side of the KZ400S front
hub is of different construction, and is used to protect
the speedometer gear. The rubber part seals the opening
by pressing outward against the brake panel.

A wheel bearing is fitted in both sides of each hub
and in the rear wheel coupling. Since worn wheel
bearings will cause play in the wheel, vibration, and
instability, they should be cleaned, inspected, and
greased periodically.

Grease Seal

3. Metal Band —
2. Secondary Lip 4, Wire Spring Band

|. Primary Lip

Inspection and lubrication

If the grease seals are examined without removing
the seals themselves, look for discoloration (indicating
the rubber has deteriorated), hardening, damage to the
internal ribbing, or other damage. If the seal or
internal ribbing has hardened, the clearance between the
seal and the axle sleeve will not be taken up, which will
allow dirt and moisture to enter and reach the bearing.
Whenever in doubt as to its condition and whenever the
seal is removed for greasing the bearing, the seal should
be replaced. The seals are generally damaged upon
removal.

Since the wheel bearings are made to extremely close
tolerances, the wear cannot normally be measured. Wash
the bearing with a high flash point solvent of some kind,

Table 71 Grease Seals, Wheel Bearings
Front Wheel (KZ400D

Bearing

Grease Seal

[wrc2ae27 | wrcaosee |wocssee7 | wrcasaae | wresssa7| — | —

e
i
ry F

#6303

dry it (do-not spin it while it Is dry), and oil it, Spin it
by hand to check-its condition. If it is noisy, does not
spin smoothly, or has any rough spots, it must be re.
placed, If the same bearing is to be used again, re-wash
it with ahigh flash point solvent of some kind, dry it, and
pack it with good quality bearing grease before instal-
lation. Turn the bearing around by hand a few times
to make sure the grease is distributed uniformly inside
the bearing, and wipe the old grease out of the hub
before bearing installation. Clean and grease the wheel-
bearings and the front hub gear housing (speedometer
gear) in accordance with the periodic maintenance chart
(Pg. 180).

REAR WHEEL COUPLING

The rear wheel coupling connects the rear sprocket to
the wheel, The forces that are transmitted between the
rear sprocket and the rear hub are transmitted through
rubber shock dampers in the coupling to absorb some of
the shock resulting from sudden changes in torque due
Lo acceleration or braking.

y |

Jf t- — F. ta)
ree ——— —
ar i, _/{ Rubber Damper:
Ps | $ =F? _—

Damper inspection

Remove the rear wheel coupling (Pg. 86), and inspect
the rubber dampers.

Replace the dampers if any appear damaged or
deteriorated.

DRIVE CHAIN

The drive chain used to transmit the engine power to
the rear wheel is the Enuma EK530SH-G 100 link chain.
This chain is provided with a master link to facilitate
removal and replacement. To minimize any chance of
the master link dislodging, the master link is fitted with
the closed end of the “U" pointed in the direction of
chain rotation. See Fig, 490,

Rear Wheel wal

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Direction of Chain Rotation

Chain construction is shown in Fig. 493. Most
chain wear occurs between the pins and bushings, and
between the bushings and rollers, rather than on the
outside of the rollers, This wear causes the chain to
lengthen. If the chain is left unadjusted, the lengthening
will lead to noise, excessive wear, breakage, and dis-
engagement from the sprockets, If the chain is allowed
to wear too much, the distance from roller to roller ts
so much greater than the distance between each tooth
of the sprocket that the wear rapidly accelerates.

The rate of wear can be greatly reduced, however,
by frequent and adequate lubrication, espeically between
the side plates of the links so that oi] can reach the pins
and bushings inside the rollers.

Wear

When the chain has worn so much that it is more
than 2% longer than when new, it is no longer safe for
use and should be replaced, Whenever the chain is
replaced, inspect both the engine and rear sprockets,
and replace for new ones if necessary. Overworn
sprockets will cause a new chain to wear quickly.

Since jt is impractical to measure the entire length
of the chain, determine the degree of wear by measuring
a 20 link length of the chain, Stretch the chain taut
either by using the chain adjuster, or by hanging a
lO kg weight on the chain. Measure the length of 20
links on a straight part of the chain from pin center of
the Ist pin to pin center of the 21st pin. Since the chain
may wear unevenly, take measurements at several places.
lf any measurement exceeds the service limit, replace
the chain.

NOTE: The drive system was designed for use with the
Enuma EK530SH-G 100 link chain, For maximum
strength and safety, the Enuma EK530SH-G 100 link
chain must be used for replacement.

Drive Chain

Measure this length

MAINTENANCE 139

Table 72 Drive Chain Length

| Standard | _ Service Limit _|

Lubrication

In order for the chain to function safely and wear
slowly, it should be properly lubricated in accordance
with the periodic maintenance chart (Pg. 180). Lubri-
calion is also necessary after riding through rain or on
wet roads, or any time that the chain appears dry. Any-
time that the motorcycle including the chain has been
washed, the chain should be adequately lubricated on
the spot in order to avoid rust.

492

if

\\ Side Plate

ry
i

f
‘y
/ Roller

Bushing

140 MAINTENANCE

The chain should be lubricated with a lubricant which
will both prevent the exterior from rusting and also
absorb shock and reduce friction in the interior of the
chain. An effective, good quality lubricant specially
formulated for chains is best for regular chain lubrication,
If a special lubricant is not available, a heavy oil such as
SAE 90 is preferred to a lighter oil because jt will stay
on the chain longer and provide better |ubrication.
Apply the oil to the sides of the rollers and between
the side plates of the Jinks so that oil will penetrate
to the pins and bushings where most wear takes place.
Wipe off any excess oil.

Dirt will cling to the oil and act as an abrasive,
accelerating chain wear, Whenever the chain becomes
particularly dirty, it must be cleaned in Kerosene and
then soaked in a heavy oil. Shake the chain while it is
in the oil so that ot! will penetrate to the inside of the
rollers. If choosing to boil the chain in grease, better oil
penetration to the interior is achieved, bul care must be
taken not to overheat the grease.

SPROCKETS

There are two sprockets for the drive chain, A for-
ward sprocket, or engine sprocket, is mounted on the
end of the output shaft and is used to drive the chain.
A rear sprocket is connected to the_rear—wheel hub
through the rear wheel coupling and is driven by the
chain to turn the rear wheel.

Sprockets that have become excessively worn cause
noise with the chain and greatly accelerate chain and
sprocket wear, The sprockets should be checked for
wear any time that the chain is replaced. A warped
rear sprocket destroys chain alignment such that the
chain may break or jump from the sprockets when
traveling at high speed. The sprockets should be checked
for wear and the rear sprocket for warp any time that
the chain is replaced.

Sprocket wear

Visually inspect the sprocket teeth. If they are worn
as illustrated, replace the sprocket.

Sprocket Teeth

(a

Worn Teeth

Rotation

NOTE: I! a sprocket requires replacement, the chain is
probably worn also, Upon replacing a sprocket, inspect
the chain,

Measure the diameter of the sprocket at the base of
the tecth. If the sprocket is worn down to less than the
service limit, replace the sprocket.

*Table 73 Sprocket Diameter
[Standard | Service Limit

Rear sprocket warp

Elevate the rear wheel so that it will turn freely, and
sel a dial gauge against the rear sprocket near the teeth
as shown in Fig. 496. Rotate the rear wheel, The
difference between the highest and lowest dial gauge
reading is the amount of runout (warp).

If the runout exceeds the service limit, replace the
rear sprocket,

ry

a

=m"

Table 74 Rear Sprocket Warp

Standard Service Limit

under 0.3 mm

DISC BRAKE (Only on KZ400D)

A hydraulic disc brake is used on the front wheel
for its superior braking performance and high reliability.
[he major components of the disc brake are the brake
lever, master cylinder, brake line, caliper assembly, and
disc, The brake lever ts pulled to pressurize the brake
fluid to move a piston in the master cylinder, Fluid
pressure operates the front brake light switch and is
transmitted through the brake line to operate the caliper.
The switch turns on the brake light, and the caliper
grips the disc attached to the front wheel, slowing wheel
rotation,

http://www.kz400.com MAINTENANCE 141

@

Master Cylinder (KZ400D)

. Master Cylinder Body
. Check Valve

. Spring

. Spring Seat

. Primary Cup

. Secondary Cup
Piston

. Stopper, Piston

. Retaining Ring
10. Dust Seal

11. Stopper, Dust Seal
12. Cap

13. Ring Plate

14. Diaphragm

15. Relief Port

16, Pressure Chamber
17. Reservoir

18. Supply Port

19. Non-return Valve

Woy DAnAbwh =

Caliper (KZ400D)

498

20, Holder
21, Caliper
22. Bleed Valve
23, Bleed Valve Cap
J4. Piston
25. Fluid Seal
26, Piston Dust Seal
27, Anti-Squeak Shim
28. Pad A
29. Pad B
30, Metal Disc
| ie 31, Screw
29 28) (27) (26) ‘25 32, Lock Washer
33, O Ring
34, Allen Bolt

http://Awww.kz400.com

142 MAINTENANCE

The brake fluid is an extra heavy duly type with
a high boiling point to withstand the heat produced
from friction of the caliper pads on the disc. Since
the boiling point and thus the performance of the fluid
would be reduced by contamination with waler vapor
or dirt from the air, the reservoir is sealed with a rubber
diaphragm under the cap, This cap seal also prevents
fluid evaporation and spillage should the motorcycle fall
over, The fluid is further protected by rubber seals in
the caliper assembly and al the master cylinder brake
line fitting.

The master cylinder assembly includes the reservoir,
piston, primary and secondary cups, non-return valve,
check valve, and spring. The reservoir has two holes
at the bottom: a relatively large supply port to supply
fluid to the lines and a small relief port to admil excess
fluid from the line, The primary and secondary cups
stop the fluid from leaking back around the piston while
the piston is moving forward Lo pressurize the line,
The check valve stops fluid from suddenly returning from
the brake line when the lever is released, and thereby
smooths brake operation. The non-return valve is in the
head of the piston; it stops backward fluid flow when
the brake is applied, but when the brake lever is released,
allows flow around the cup to fill the vacuum in front
of the piston so that the piston can return easily,

The caliper assembly includes pad A, pad B, and the
piston, which is inside the caliper cylinder, Through
the caliper run two shafts, which also pass through the
caliper holder to mount the assembly to the left fork
shock absorber, When the piston forces pad A against
the disc, the shaft portion of the caliper assembly slides
through the halder such that pad B is also forced against
the disc, both brake pads being kept parallel to the disc.

Unlike a drum-type brake, the components of the
disc brake which perform the actual braking action,
Le., the dise and pads, are open to direct contact with
the air flow past the motorcycle. This provides for
excellent dissipation of the heat from brake friction,
and minimizes any possibility of brake fade common Lo
drum brakes,

When fluid pressure develops in the cylinder, the
piston is pushed exerting pressure against the brake pad,
which in turn presses against the brake disc, The
pressurized fluid is prevented from leaking by a fluid
seal filled into the cylinder wall. The seal presses

Rubber Seal

Fluid Seal

el] |
Ss

-— -—

SS

Y

SS

MQ

—— —

a,

SS
WE

\
WS

Dust Seal Dust Seal Fluid Seal

against the piston, and instead of sliding when the
piston moves, the seal is only distorted, allowing no
fluid leakage at all, When the brake lever is released
and fluid pressure lowers, the elasticity of the seal
returns the piston to its original position. After the
brakes are used for a while and the pads wear slightly,
the rubber seal will no longer be able to be distorted
the additional amount that the piston travels. Instead,
when piston travel forces the seal past its limit, the seal
slips slightly on the piston, and then returns the piston
to a new rest position not as far in. A small amount of
fluid from the reservoir supplements the fluid in the
brake line to compensate for the difference in piston
position, Consequently, the length of the brake lever
stroke remains unchanged, and the brake never needs
adjustment,

The rubber seal and the cup at the head of the master
cylinder piston are made of an fluid and heat resistant
rubber composition for best performance and to prevent
contamination of the brake fluid by rubber deteriora-
tion. For this reason only standard parts should be used,

Braking Stroke

When the brake lever is pulled, the piston 7 in the
master cylinder (1) is pushed and moves forward against
the force of the return spring 3). At this time, the
primary cup 5 at the head of the piston closes the
small relief port 05, which connects the pressure
chamber 36 and the reservoir i7. Until this port is
fully closed, the brake fluid does not start being pres-
surized, in spite of the forward movement of the piston.

The pressure stroke starts as soon as the relief port
is closed, The piston compresses the brake fluid, which
is being used as the pressure medium, forcing it through
the check valve (2) and out into the brake line. The
pressure is transmitted in the line to the cylinder portion
of the caliper assembly, where it forces the piston to-
wards the disc. Pad A 2@ at the end of the piston is
forced against the disc, but, since the disc is immovable,
further pressure cannot move the pad any farther.
Instead, the entire caliper assembly moves in the
opposite direction such that pad B is also forced against
the disc, In this manner, the disc is gripped between
the two pads, and the resulting friction slows wheel
rotation,

Braking Release Stroke

When the brake lever is released, the piston in the
master cylinder is quickly returned toward its rest
position by the spring 3), and brake fluid pressure
in the line and in the caliper master cylinder drops.
The elasticity of the fluid seal 25 in the cylinder then
returns the piston, This leaves no pressure against either
pad A or B so that slight friction against the disc pushes
them both a hairbreadth away from the disc,

As the master cylinder piston moves back further,
the brake fluid in the line (which still has some pressure)
rushes to fill the low pressure area in front of the primary
cup at the piston head, But the fluid is prevented from
moving quickly by the check valve, and the low pressure
area in front of the piston is not relieved. At this time,

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fluid from the reservoir flows through the large supply
port “@ into the space between the primary and second-
ary cups (6), through the non-return valve 19 , and passes
around the edges of the primary cup to fill the vacuum.
When the piston_has_returned to its rest position
against the stopper (8), the small relief port is uncovered,
and, as the brake fluid returns from the line through
the check valve, excess fluid passes through the relief
port into the reservoir until the brake line pressure re-
Lurns to zero,

Brake Fluid

When the brake is applied, heat is generated by the
friction between the disc and the brake pads, While
much of this heat is immediately dissipated, some of
it Is transmitted to the brake fluid and may raise fluid
temperature to as high as 150°C (300°F) during brake
operation, This temperature could boil the brake fluid
and cause a vapor lock in the lines unless fluid with a
high boiling point is used and has been kept from being
contaminated with dirt, moisture, or a different type of
fluid. Poor quality or contaminated fluid can also deteri-
orate the rubber parts of the brake mechanism, although
a special rubber is used to make them resistant to deteri-
oration from contact with the recommended brake
fluids.

Brake Fluid Boiling Point 600
250°
pe al —}- (Seen ——+
Is

12129 0% = 1% ’<, a ee | 5%
Percentage of Moisture

The graph of Fig. 500 shows how brake fluid contam-
ination with moisture lowers the fluid boiling point.
Although not shown in the graph, the boiling point also
lowers as the fluid. gets old, is contaminated with dirt,
or if two different types of brake fluid are mixed.

Changing the brake fluid

The brake fluid should be changed in accordance with
the periodic maintenance chart (Pg. 180) and whenever
it becomes contaminated with dirt or water,

@Attach a clear plastic hose to the bleed valve on the
caliper, and run the other end of the hose into a
container,

@Open the bleed valve (counterclockwise to open), and
pump the brake lever until all the fluid is drained from
the line,

MAINTENANCE 143

®Close the bleed valve, and fill the reservoir with fresh
brake fluid.

@Open the bleed valve, squeeze the brake lever, close
the valve with the lever held squeezed, and then quickly
release the lever. Repeat this operation until the brake
is filled and fluid starts coming out of the plastic hose.
Replenish the fluid in the reservoir as often as necessary
to keep it from running completely out,

Bleed the air from the lines.

Bleeding the brake

The brake fluid has a very low compression coef-
ficient so that almost all the movement of the brake
lever is transmitted directly to the caliper for braking
action, Air, however, is easily compressed, When air
enters the brake lines, brake lever movement will be
partially used in compressing the air, This will make the
lever feel spongy, and there will be a loss in braking
power,

Bleed the air from the brake whenever brake lever
action feels soft or spongy, after the brake fluid is
changed, or whenever a brake line fitting has been
loosened for any reason.

@®Remove the reservoir cap, and check thal there is
plenty of fluid in the reservoir. The fluid level must
be checked several times during the bleeding operation
and replenished as necessary. If the fluid in the reser-
voir runs completely out any time during bleeding, the
bleeding operation must be done over again from the
beginning since air will have entered the line,

eWith the reservoir cap off, slowly pump the brake lever
several limes until no air bubbles can be seen rising up
through the fluid from the holes at the bottom of the
reservoir, This bleeds the air from the master cylinder
end of the line,

Reservoir

@Replace the reservoir cap, and connect a clear plastic
hose to the bleed valve at the caliper, running the other
end of the hose into a container. Pump the brake lever
a few times until it becomes hard and then, holding the
lever squeezed, quickly open (turn counterclockwise)
and close the bleed valve. Then, release the lever.
Repeat this operation until no more air can be seen
coming oul into the plastic hose. Check the fluid
level in the reservoir every so often, replenishing it
as necessary.

http://www.kz400.com

144 MAINTENANCE

WARNING
When working with the disc brake, observe the
precautions listed below.
1, Never reuse old brake fluid.
2. Do not use fluid from a container that has been
left unsealed or that has been open a long time.
3. Do not mix two types of fluid for use in the brake,
This lowers the brake fluid boiling point and could
cause the brake to be ineffective. |t may also cause
the rubber brake parts to deteriorate. Recom-
mended fluids are given in the table.
NOTE: The type of fluid originally used in the
disc brake is not available in most areas, but it
should be necessary to add very little fluid before
the first brake fluid change. After changing the
fluid, use only the same type thereafter.

*Table 75 Recommended Disc Brake Fluid
Atlas Extra Heavy Duty
Shell Super Heavy Duty
Texaco Super Heavy Duty
Wagner Lockheed Heavy Duty
Castrol Girling-Green
Castrol GT (LMA)
Castro! Disc Brake Fluid

The correct fluid will come in a can labeled
D.O.T.3. Do not use fluid that does not have
one of these markings.

eWhen air bleeding is finished, replace the rubber cap
on the bleed valve, and check that the brake fluid is
filled to the line marked in the reservoir (handlebar

turned so that the reservoir is level),

Level Line

Master cylinder parts wear

When master cylinder parts are worn or damaged,
proper brake fluid pressure cannot be obtained in the
line, and the brake will not hold,

Table 76 Master Cylinder Parts

_ Measurement _ = Standard
Cylinder inside diameter | 14,000~ 14,043 mm

Piston outside diameter 13.957~ 13.984 mm
Primary, secondary cup diameter | 14.65~15.15 mm

. Don’t leave the reservoir cap off for any length of
time to avoid moisture absorbing into the fluid.

. Don’t change the fluid in the rain or when a strong
wind is blowing,
Except for the disc pads and disc, use only disc
brake fluid, isopropyl alcohol, or ethy! alcohol for
cleaning brake parts, Do not use any other fluid
for cleaning these parts. Gasoline, motor oil, or
any other petroleum distillate will cause deterio-
ration of the rubber parts, Oil spilt on any part
will be difficult to wash off completely and will
eventually reach and break down the rubber used
in the disc brake,

. When handling the disc pads or disc, be careful
that no disc brake fluid or any oil gets on them.
Clean off any fluid or oil that inadvertently gets
on the pads or disc with a high flash point solvent
of some kind. Do not use one which will leave
an oily residue. Replace the pads for new ones if
they cannot be cleaned satisfactorily.

. Brake fluid quickly ruins painted surfaces; any
spilt fluid should be completely wiped up im-
mediately,

. If any of the brake line fittings or the bleed valve
is Opened at any time, AIR MUST BE BLED
FROM THE BRAKE.

. When installing or assembling the disc brake,
tighten the disc brake fittings to the values given
in Table 2. Improper torque may cause the brake
to malfunction.

If the small relief port becomes plugged, especially
with a swollen or damaged primary cup, the brake pads
will drag on the disc,
eCheck that there are no scratches, rust or pitting on

the inside of the master cylinder, and that it is not
worn pasl the service limit,

eCheck the piston for these same faults,

@lnspect the primary and secondary cups, If a cup is
worn, damaged, softened (rotted), or swollen, replace
it. When inserting the cup into the cylinder, see that
it is slightly larger than the cylinder (standard values
given in the table), If fluid leakage is noted at the brake
lever, the cups should be replaced, (The secondary
cup js part of the piston assembly, Replace the piston
if the secondary cup requires replacement),

eCheck that the spring is not damaged and js not shorter
than the service limit.

@Replace the dust seal if damaged,

Caliper parts wear
Inspect the pads for wear. If either pad is worn
down through the stepped portion, replace both pads

pervice ae }

13 90 mm
14,50 mm

Spring length (free)

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as a set. If any grease or oil spills on the pads, wash
it off with trichloroethylene or a high flash point solvent
af some kind. Do not use one which will leave an oily
residue, If the oil cannot be thoroughly cleaned off,

replace the pads.

Stepped Portions

The fluid seal around the piston maintains the proper
pad/disc clearance. If this seal is not satisfactory, pad
wear will increase, and constant pad drag on the disc will
raise brake and brake fluid temperature.

Replace the fluid seal under any of the following
conditions: (a) fluid leakage around pad A; (b) brakes
overheat; (c) there is a large difference in A and B pad
wear; (d) the seal is stuck to the piston. If the fluid
seal is replaced, replace the dust seal as well. Also re-
place both seals every other time the pads are changed.

Check to see if the caliper holder shafts are not
badly worn or stepped. If the shafts are damaged,
replace the shafts and the caliper holder.

Replace the cylinder and piston if they are worn
out of tolerance, badly scored, or rusty.

Check both seals and the O ring, and replace any
that are cracked, worn, swollen or otherwise damaged.

Table 77 Caliper Parts
Cylinder
inside diameter

38.17 mm

38.10~38.15 mm

outside diameter 31.97 ~ 38.02 mm

Brake line damage

The high pressure inside the brake line can cause fluid
to leak or the hose to burst if the line is not properly
maintained.

Bend and twist the rubber hose while examining it.
Replace it if any cracks or bulges are noticed,

The metal pipe is made of plated steel, and will
rust if the plating is damaged, Replace the pipe if it ts
rusted or cracked (especially check the fittings), or if
the plating is badly scratched,

Disc wear, warp

Besides wearing down, the disc may warp, A warped
disc will cause the brake pads to drag on the disc and
wear down both the pads and disc quickly. Dragging

will also cause overheating and poor braking efficiency.

Service Limit |

MAINTENANCE 145

Poor braking can also be caused by oi! on the disc.
Oil on the disc must be cleaned off with trichloroethylene
or a high flash point solvent of some kind. Do not use
one which will leave an oily residue.

Jack up the motorcycle so that the front wheel is
off the ground, and turn the handlebar fully to one side.
Set up a dial gauge against the disc as illustrated, and
measure disc runout, If runout exceeds the service limil,
replace the disc,

ander 0.1 im

Measure the thickness of the disc at the point where
itis has worn the most, Replace the disc if il has worn
past the service limit.

Table 79 = Dise Thickness

6.90~7.10 mm

BRAKES

The front wheel is equipped with a two-leading-shoe
type of drum brake (only on KZ400S; the KZ400D has
a disc brake on the front) and the rear wheel is equipped
with a leading-trailing type of drum brake, “T wo-leading-
shoe" means that both brake shoes lead, thatis, expand
against the drum in the direction of drum rotation.
“Leading-trailing” means that one of the two brake
shoes leads, expanding against the drum in the direction
of drum rotation, and the other shoe trails, expanding
in the direction opposite drum rotation,

http://www.kz400.com

146 MAINTENANCE

Brake (KZ400S Front)

Direction of Rotation 606)

Leading Shoes

Brake (Rear)
Direction of Rotation 50

Leading Shoe

Trailing Shoe

The force applied by the rider when braking is trans-
mitted to the interior of the brake by a camshaft, The
force applied at the brake pedal or brake lever is
transmitted by a rod or a cable to the cam lever which
then turns the camshaft. When the camshaft rotates,
the large portion of the cam is forced between the two
brake shoes, Since the shoes are only held together
away from the drum by a spring, the cam overcomes
spring tension and pushes the shoes outward against the
drum. The leading shoe rotates in direction “A” and the
trailing shoe in direction "B" as shown in the diagrams.

The friction between the linings and the drum, which
decelerates the motorcycle, gradually wears down the
brake shoe linings. On the outside of the brake panel

is a brake lining wear indicator, which, as the brake is
applied, moves in direct proportion to the distance that
the brake shoe linings move to reach the brake drum. As
the linings wear down, the lining surface has farther to
travel before reaching the drum. The indicator accord-
ingly travels farther until it finally points just to the
left of the “U" in USABLE when the lining wear has
reached the service limit.

Due to wear of the brake drum, shoe linings, and cam,
periodic brake adjustment is required. However, if the
brake parts become overworn, adjustment will not be
sufficient to ensure safe brake operation. Not only can
overworn parts crack (drum) and otherwise suffer damage
as they lose their braking effectiveness, but, if the cam
wears to the point where it turns nearly horizontal when
the brake is fully applied, the brake may lock in the
operated position, or brake pedal return may be very
sluggish. All brake parts should be checked for wear
in accordance with the periodic maintenance chart (Pg.
180),

Brake drum wear

Measure the inside diameter of the brake drum with
calipers to determine wear, Since uneven drum wear will
decrease braking effectiveness, take measurements at a
minimum of two places. If the drum is worn unevenly
or if it is scored, turn the drum down on a brake drum
lathe or replace the hub, (Do not turn it down to the
service limit, and do not turn it down if any diameter
measurement exceeds the service limit). If any diameter
measurement exceeds the service limit, replace the hub
for a new one,

Table 80 Brake Drum Inside Diameter
Standard

s | Service Limit |
| 180,0~ 180.2 mm 180.75 mm

Brake shoe lining wear

Check the thickness of the brake linings, and replace
both shoes as a set if the thickness at any point is less
than the service limit. If the thickness of the brake
linings is sufficient, check the linings for uneven wear,
and file or sand down any high spots. With a wire brush,
remove any foreign particles imbedded in the lining
surface. Wash off any oil or grease with a high flash
point solvent of some kind. Do not use one which will

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leave an oily residue. In case the linings are damaged
or the surface cannot be restored by sanding and clean-
ing, the shoes must be replaced.

Brake Lining

Table 81 Brake Lining Thickness

Brake shoe spring tension

If the brake springs become stretched, they will not
pull the shoes back away from the drum after the brake
lever or pedal is released, causing the shoes to drag on
the drum. Remove the springs, and check their free
length with vernier calipers, If either is stretched beyond
the service limit, replace both springs.

Brake Spring 10

Table 82 Brake Spring Free Length

| | Standard | Service Limit |
| Front (K2400S) | 46.7~47.3 mm
as es

Camshaft, shaft hole wear

Excessive shaft to hole clearance will increase cam-
shaft play and reduce braking efficiency.

Measure the shaft diameter with a micrometer, and
replace it if it is worn down to less than the service
limit.

MAINTENANCE 147

Brake Camshaft pes §1)

Measure the inside diameter of the camshaft hole, and
replace the brake panel if the hole is worn past the
service limit,

anal ) | 14.957~14.984 mm | 14.83 mm
ShaftHole — | eee
|(KZ400S Front) | 15-000~15.027 mm

[Camshaft (Rear) | 16.957~16.984 mm | 16.83 mm_
| Shaft Hole (Rear)| 17.000~17.027 mm | 17.18 mm

Lubrication

Every time that the brake is disassembled, and
in accordance with the periodic maintenance chart
(Pg. 180), wipe out the old grease, and re-grease the
brake pivot points. Apply grease to the brake shoe
anchor pins, spring ends, and cam surface of the
camshaft, and fill the camshaft groove with grease.
Do not get any grease on the brake shoe linings, and
wipe off any excess grease so that it will not get on
the linings or drum after brake assembly.

KZ400S Front

Camshaft

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148 MAINTENANCE

STEERING STEM

The steering stem supports the handlebar and front
fork shock absorbers, and turns inside the frame head
pipe. Ball bearings in the upper and lower ends of the
head pipe enable the steering stem to turn smoothly
and easily,

The steering stem itself does not wear, but it may
become bent. If it becomes bent, the steering will be
stiff, and the bearings may become damaged.

Steering Stem 615)

())

1. Stem Head Bolt 9, Lower Inner Race
2. Washer 10. Steel Balls

3. Washer 11. Stem Base

4. Stem Head Clamp Bolt 12, Stem Head

5. Steering Stem Lock Nut 13. Upper Inner Race
6, Steering Stem Cap 14. Upper Outer Race
7. Steel Balls 15. Frame Head Pipe

8. Lower Outer Race 16. Steering Stem

The steering stem will require periodic adjustment as
it becomes loose due to bearing wear, Overtightening
during adjustment, however, will make the steering stiff
and cause accelerated bearing wear. Lack of proper
lubrication will also bring about the same results.

From overtightening or from a heavy shock to the
steering stem, the bearing race surfaces may become
dented. Damaged bearing races will cause the handlebar
to jerk or catch when turned.

Table 84 Bearing Ball Specifications

| Size | Number _|

ia Upper & : |

Steering stem warp
Examine the steering stem, and replace it if it is bent.

Bearing wear, damage

Wipe the bearings clean of grease and dirt, and
examine the races and balls, If the balls or races are
worn, or if either race is dented, replace both races and
all the balls for that bearing as a set.

Bearing lubrication

In accordance with the periodic maintenance chart
(Pg. 180), and whenever the steering stem is disassembled,
the steering stem bearings should be relubricated.

Wipe all the old grease off the races and balls, washing
them in a high flash point solvent of some kind if neces-
sary. Replace the bearing parts if they show wear or
damage. Apply grease liberally to the upper and lower
races, and stick the bearing balls in place with grease.

Bearing Balls 610

FRONT FORK

Front fork construction is shown in Fig. 517. It
consists of two shock absorbers connected to the frame
head pipe by the stem base and stem head bracket, It
accomplishes shock absorption through spring action, air
compression in the inner tube, and resistance to the flow
of the oil forced into the cylinder by tube movement.

Front Fork

—
a

f—a fA
ee es NES
ed ee =

SS
&
= ee

4

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. Lop Bolt

. Upper Clamp Bolt
. Ring Cap

. Fork Cover

. Damper Ring

. Damper

. Stem Head Clamp Bolt
. O Ring

. Spring

Q. Steering Stem

. Stem Base Cover
. Lower Clamp Bolt
. Dust Seal

Gp

. Oil Seal

Inner Tube

. Outer Tube
. Piston

. Piston Ring
. Spring

. Spring Seat
. Valve

. Collar

. Cylinder

. Cylinder Base
. Gasket

. Allen Bolt
. Stem Head

MAINTENANCE 149

Front Spring Force 518

| Ae

a

Weight(kg)——=

-11 9. 50 98.5~ 100 120

Compression (mm)

Each shock absorber is a telescopic tube including an
inner tube (6), outer tube (7), cylinder 24, piston 48 ,
collar 23), and cylinder base 25). The inner tube fits into
the outer tube, altering its position in the outer tube as
the tube arrangement absorbs shocks. The cylinder is
fixed to the bottom of the outer tube and the piston
(equipped with a piston ring 19) is secured to the top
of the cylinder. The collar (coupled with a non-return
valve 22), fixed in the lower end of the inner tube,
forms the upper part of the lower chamber and together
with the piston helps seal the upper chamber. The collar
and cylinder base configuration functions to form an oil
lock at the end of the compression stroke to prevent the
inner tube from striking the bottom. Vertically arranged
orifices (2) in the upper part of the cylinder bring about
an oil Jock at the end of the extension stroke to prevent
the inner tube from striking the top,

Ojl is prevented from leaking out by the oil seal (5,
which if fitted at the upper end of the outer tube, Adust
seal 43) on the outside of the tube keeps dirt and water
from entering and damaging the oil seal and tube surface.

Compression stroke

Whenever a load is placed on the front fork and when-
ever the front wheel receives a shock, the inner tube (0
moves down inside the outer tube 4), compressing
both the spring (1) and the air in the inner tube, At the
same time, low pressure (suction) is created in an enlarg-
ing chamber (upper chamber) formed between the inner
tube and the cylinder (8) , and draws in oil from a
diminishing chamber (lower chamber) formed between
the outer tube and the cylinder, As the lower chamber
shrinks in size with oil passing freely through the non-
return valve (6) into the upper chamber, oil also passes
freely through the cylinder lower orifices into the
cylinder as the inner tube approaches the cylinder base
(9). Near the end of the compression stroke, the
clearance between the tapered-out cylinder base and the
collar at the lower end of the inner tube approaches
zero. The resulting resistance to the flow of oil through
this small space slows the downward movement, finally
forming an oil lock to finish the compression stroke.

150 MAINTENANCE

Compression Stroke

-Seennuwsewn-—

. Spring
. Piston
. Piston Ring
. Spring
. Spring Seat

3°
—s

Valve

. Collar

. Cylinder

. Cylinder Base
. Inner tube

. Outer tube

http://www.kz400.com

619

Outer Tube Movement

Extension Stroke

y,
2,
5.
4,
eh
6
7
5.
9
10)

lI

Spring
Piston
Piston Ring
Spring
Spring Seat

_ Valve
. Collar

Cylinder

. Cylinder Base
. Inner tube
. Outer tube

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Outer Tube Movement

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Extension stroke

Following the compression stroke is the extension
stroke, in which the inner tube is pushed back out by
the compressed spring. As the tubes move apart, the
upper chamber grows smaller, forcing the oil through
the cylinder upper orifices since the oil cannot return the
way it came through the non-return valve. These small
holes resist the oi! flow into the inner tube, damping fork
extension, Near the end of the extension stroke both the
cylinder spring and the arrangement of the cylinder upper
orifices provide further resistance to extension. As the
collar rises reducing the size of the upper chamber, one
orifice is eliminated as an upper chamber outlet, which
reduces the oil flow slowing extension. When the other
orifice is eliminated, an oil lock forms, which finishes
the extension stroke,

Either too much or too little oil in the shock absorbers
will adversely affect shock damping. Too much oil or
too heavy an oil makes action too stiff: too little oil or
Loo light an oi! makes the action soft, decreases damp-
ing potential, and may cause noise during fork move-
ment,

Contaminated or deteriorated oil will also affect
shock damping, and, in additon, will accelerate internal
wear. The fork oil should be changed in accordance
with the periadic maintenance chart (Pg. 180) or sooner
if the oi! appears dirty.

A bent, dented, scored, or the othersiwe damaged
inner tube will damage the oi! seal, causing oil leakage.
A badly bent inner tube may cause poor handling.

Fork oil

To check the fork oil level, first place a jack or stand
under the engine so that the front wheel is raised off
the ground. Remove the top bolt from the inner tube,
Insert a rod down into the tube, and measure the distance
from the top of the inner tube to the oil level, If the oil
is below the correct level, add enough oi! to bring it up to
the proper level, taking care not to overfill.

4 |

*
a

Table 85 Fork Oil

T : Amount
ype per side “
| 155~165 cc |
SW 161~166co | -O8CO™™ = Gos _|

lo drain out the old oil, remove the drain bolt
lram the lower end of the outer tube on each side,
With the front wheel on the ground, push down on the
handlebar a few times to pump out the oil. Replace

Oil level from —
top of inner tube |

MAINTENANCE 151

the drain bolts, remove the top bolt from each side,
and pour in the specified type and amount of oil, Then
replace the top bolts, tightening them with 2.5 ~ 3,0
ft-lbs) of torque,

kge-m (18 ~ 22

Spring tension

Since the spring becomes shorter as it weakens, check
its Iree length to determine its condition, If the spring
of either shock absorber is shorter than the service
limit, it must be replaced, If the length of a replacement
spring and that of the remaining spring vary greatly, the
remaining spring should also be replaced in order to
keep the shock absorbers balanced for motorcycle stabil-
ty.

Table 86 Fork Spring Free Length
Standard |

Inner tube damage

Visually inspect the inner tube, and repair any
damage. If the damage is not repairable, replace the
inner tube, Since damage to the inner tube damages the
oi! seal, replace the oil seal whenever the inner tube is
repaired or replaced,

SEUVICe Limit

REAR SHOCK ABSORBERS

The rear shock absorbers serve to dampen shock
transmitted to the frame and rider from the rear wheel,
For this purpose they are connected between the frame
and the rear end of the swing arm. Shock absorption is
perlormed by the spring and by the resistance to the
flow of oil inside each unit, Shock absorption is further

152 MAINTENANCE
Rear Shock Absorber

®

SS
=

http://www.kz400.com

|. Rubber Bushing
2. Nut

3, Stopper Rubber
4, Cover

5. Piston Rod
6, Outer Spring

7, Oil Seal

8. Inner Spring

9, Check Valve

10. Piston

11. Spring Seat

12, Outer Shell

13. Rubber Bushing
14. Collar

aided by the use of rubber bushings in both the upper
and lower shock absorber mountings.

Since the rear shock absorbers are sealed units which
cannot be disassembled, only external checks of oper-
ation are necessary. With the shocks removed, compress
each one and see that the compression stroke is smooth
and that there is damping besides spring resistance to
compression, When the unit is released, the spring should
not suddenly snap it to full length. It should extend
smoothly with notable damping. When the shock
absorber is operated, there should be no oil leakage.
If either shock absorber does not perform all of these
operations satisfactorily, or if one unit feels weaker than
the other, replace both shock absorbers as a set. If only
one unit ts replaced and the two are not balanced, motor-
cycle instability at high speeds may result.

Shock absorber spring force for the 5 different settings
is shown in the graph.

Rear Spring Force 25)

—— Weight(kg)

1970 2 40 60 = g0

Compression(mm)

Bushings

Check the rubber bushings, and replace any that
are worn, cracked, hardened, or otherwise damaged.

SWING ARM

The swing arm is designed to work with the shock
absorbers to dampen the shock to the frame from the
rear wheel. The rear of the swing arm is connected to
the frame by the rear shock absorbers, while the front
end pivots on a shaft connected to the frame. When the
rear wheel receives a shock, the swing arm, pivoting on
its shaft, allows the wheel to move up and down in rela-
tion to the frame within the limits of the shock
absorbers,

Wear takes place where the short sleeves and bushes
rub together. If wear has progressed such that the swing
arm has become loose, the motorcycle will be unstable,
especially at high speeds. To minimize wear, the swing
arm should be kept properly packed with grease.

A bent pivot shaft or twisted swing arm will also cause
instability by throwing the rear wheel out of alignment.

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MAINTENANCE 153

Swing Arm
DOD ©®@ ® ® @® 66

9 2 SSS SS ee NN
‘a: ESS GS pee ILL ST
if | )

ftneees tnd : LLIS LILI SSIS SSSI

d
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I\\I , x
. Pivot Shaft

. Distance Collar

. Sleeve

. Bush

Cap

. O Ring

. Pivot Shaft Nut

ae a

Sleeve, bush wear Table 87 Swing Arm Sleeve, Bush Diameter

Measure the outside diameter of the sleeves at both
ends with a micrometer, Replace both sleeves if the dia-
meter of either is less than the service limit or if either
shows visible damage.

Se rvice Limit

Standard —

Sleeve :
: 21.95 mm
| outside dia,
Bush
inside dia.

27.26 mm
Sleeve 626) Pivot shaft

To measure the pivot shaft runout, set the pivot
shaft on V blocks at the ends of the shaft, and set a
dial gauge to the shaft halfway between the blocks.
Turn the shaft to measure the runout. The amount
of runout is the amount of dial variation. If the shaft
runout exceeds the service limit, straighten it. If it
cannot be straightened, or if the runout exceeds 0.7
mm, replace the shaft.

7|.979~ 22,000 mm |

99,030~ 22.063 mm

Measure the inside diameter of cach bush with a
cylinder gauge. Replace both bushes if the diameter of
either exceeds the service limit. Also, replace both
bushes if either shows visible damage.

a) Pivot Shaft

Table 88 Pivot Shaft Runout

Lubrication

There is a grease fitting on the swing arm for lubri-
cation. Grease the swing arm with regular cup grease as
a part of general lubrication (Pg. 182) with the frequency
given in the periodic maintenance chart (Pg. 180), Force

http://www.kz400.com

154 MAINTENANCE

the grease into the fitting until it comes oul at both sides
of the swing arm, and wipe off any excess. If the grease
does nol come out, first check that the fitting is not
clogged with dirt or old grease. If the fitting is clear but
will still not take grease, remove the swing arm pivot
shaft, sleeves and bushes, and clean out the old grease
first,

MUFFLERS

The mufflers reduce exhaust noise and conduct the
exhaust gases back away from the rider while keeping
power loss to a minimum,

If there is any exhaust leakage where the mufflers
connect to the cylinder head, or if the gaskets appear
damaged, replace the gaskets. If either muffler is badly
damaged, dented, cracked or rusted, replace it for a new
one,

Muffler

|. Muffler
2, Baffle Tube
3. Glass Wool

DYNAMO

The dynamo generates the current required by the
electrical circuits. The generated current is a 3 phase
alternating current (AC), which is changed to direct
current (DC) by a rectifier and controlled by a 2 point
regulator to supply an even voltage to the circuit com-
ponents,

Dynamo Circuit Dynamo
[oa ie eae
= Yellow
| =| |
|
| Ags C > : | Rectifier
" :
Armature
Yellow
| Yellow
| rh VO0€
Field Col!
|
]
| Green
|

| fe a a ‘Black

Dynamo Construction

1. Armature
2. Field Coil
3. Rotor

The dynamo consists of a stationary tield coil and
armature and a revolving rotor, all of which are separately
mounted, The field coi] and armature are both mounted
in the dynamo cover, while the rotor is secured to the
left end of the crankshaft and rotates al engine rpm,

When the ignition switch is turned on, current contro}
led by the regulator flows to the field coil, and the
resulting magnetic field (that accompanies electron flow)
Is Concentrated in the rotor. Then, when starting the
engine, the kickslarler or starter motor turns the crank-
shaft, and magnetic lines of force cut through the arma-
ture windings (3) generating current. These windings
are connected in a wye connection (Fig. 533) to produce
a 3 phase alternating current (Fig, 534), Since the

632)

Regulator

http://www.kz400.com

voltages of these 3 phases overlap, there is a continuous,
even supply of current for the circuit components,

Wye Connection

0
\
| Mae he”
—120°—-— 120° —-—120° 4
ae —360" =

If the battery, rectifier, and regulator are all good
but there is low voltage or insufficient charging current,
the dynamo may be defective, A defective dynamo is
due to either an electrical short or open in the field coil
or armature, Ejther an electrical short or open will result
ina low output or no output at all,

Dynamo test
Before making this test, check the condition of the
battery (Pg, 162) and rectifier (Pg. 157), If the battery
voltage is less than 12 volts, charge the battery, Both
the oulpul voltage and output amperage is checked.
@Remove the left side cover and the headlight unit (Peg.
92), and disconnect the GP connector, which is on the
left side of the motorcycle, and the 9P connector,

Dynamo
namo Voltage Test SS
OY : - =) 4
Yellow
: 2 |
| z .
| A
i) if,
; nS ‘jj f
| Armature l
I ¥
—
| . : Yellow
| AHGOGOC
|

r--

MAINTENANCE 155

which is in the headlight housing. This removes the
load from the dynamo.
@Disconnect the rectifier white lead from the battery
+ lead.
@Set a multimeter to the 30 VDC range, and connect
its + lead to the rectifier white lead and its — lead to
chassis ground,

@®Kemove the right side cover, and disconnect the
regulator green and brown leads from the regulator
terminals marked F and | respectively, Connect the
green and the brown leads together electrically,

CAUTION: When connecting the green and the brown
leads, be certain that the connection does not get shorted
to chassis ground. Also, do not leave these leads
connected any longer than necessary; disconnect them
after finishing the test,

Rectifier

oe Ue 637)

White

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156 MAINTENANCE

®*Start the engine, run it al idling speed (1,100~ 1,300
rpm), and note the meter reading, The reading should
be 14 VDC or more. A lower reading indicates the
dynamo ts defective.

CAUTION: When or after starting the engine, DO NOT
allow the engine to run at a higher rpm (not above 2,000
rpm) in order not to damage the rectifier and other
electrical components,

eStop the engine, and connect a variable resistor (12
200W) in series with the rectifier, one lead to the
rectifier white lead and the other lead to chassis ground,

@Sei the resistor at its highest resistance, and start the
engine. While adjusting the resistor to keep the voltage
at 14.5 VDC, gradually raise the engine speed up to
5,000 rpm.

Dynamo Amperage Test 1

Dynamo = Rectifier
om eee fame iets
| Yellow
| = il
) ! |
| | | |
..
' WS DM |
Armature | | |
Yellow _
| | ’ |
| Fee Voiow ee pe
| \ 6) | ‘ ‘ é , Green
; Field Coil :
Le ne Se ~ Black
Dynamo Amperage Test 2 Dynamo Rectifier
Bh, sca abner en ee eae
~~ Yellow

| |
=
yay
ot il
ey

|

|
Yello

e®Stop the engine, disconnect the multimeter lead which
is connected to chassis ground, and disconnect the
variable resistor lead which is connected to the rectifier
white lead.

eSei the multimeter to the 30 ADC range, and connect
the meter — lead to the variable resistor. This puts
the rectifier, multimeter, and variable resistor in series,

CAUTION: Make sure that all connections are firm. A
loose connection allows the generator output voltage to
increase instantly.

*Start the engine, run it at 5,000 rpm, and note the
reading. The reading should be more than [4 ADC,
A lower reading indicates that the dynamo is defective,

eStop the engine, and disconnect the green and the
brown leads.

lf the dynamo was found to be defective, carry oul
the following checks to determine which part ts defective.

White

“| Variable
Resistor
(122 2O0W)

Voltmeter

i

—

= a =

@

He Variable =
a -
l ! - Resistor
Sian eee | = (162 200W)

http://www.kz400.com

@Disconnect the white plug on the left hand side below
the regulator,

*Sclt the multimeter to the R x | range, and measure
for continuity between each of the three armature
yellow leads (3 measurements), The readings should
be 0.4~ 0.6 ohms, If there is resistance or no meter
reading (infinity) for any two armature leads, the arma-
Lure has an open and must be replaced.

RAWASARI

pa,
Fe lige
- = irr

pr | \\y ¥

eUsing the highest resistance range of the multimeter,
measure the resistance between each of the three arma-
ture leads and chassis ground. There should be no
meter reading, Any meter reading indicates a short,
necessitating armature replacement,

@Disconnect the white plug on the right hand side below
the regulator,

@Using the R x 1 range, measure the resistance between
the field coil green lead and black lead. The resistance
should be 3.8~5.8 92. Less than this reading indicates
a short in the coil, and a higher reading or no reading
at all indicates an open. If the field coil is found to be
open or shorted, replace the field coil with a new one.

Rectifier Circuit

Black

Yellow

RECTIFIER

The rectifier is used to change the alternating current
(AC) from the dynamo to direct current (DC) for the
battery charging, ignition, lighting, and other circuits,
It contains six silicon diodes, two to rectify (change to
DC) each of the three phases of the dynamo output.
The diodes are connected in a bridge circuit arrangement
for efficient, full-wave rectification.

The reason that a diode only permits direct current
to flow in the part of the circuit in which it is connected
is that a diode conducts appreciable current only in one
direction, The current of electrons flows appreciably
only from the to the + side of the diode. However,
a defective diode will conduct in both directions (a
short) or not conduct at all (an open). If any of the
diodes is shorted or open, the voltage from the rectifier
will be below normal, and the battery may not charge
adequately,

Diode 64d)

=

Current

Batlery

Inspection

eWith the engine off, remove the left side cover, dis-
connect the rectifier white lead from the battery + side.
and disconnect the rectifier black lead.

®Remove the right side cover, and disconnect the white
plug on the left hand side below the regulator,

eUsing the R x 10 or R x 100 ohmmeter range, check
the resistance in both directions between the white lead
and each yellow lead, and between the black lead and
each yellow lead. There is a total of 12 measurements,
The resistance should be low in one direction and more
than ten Limes as much in the other direction, If any

Rectifier
ie @

MAINTENANCE 157

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158 MAINTENANCE

two leads are low or high in both directions, the rectifier
is defective and must be replaced,

NOTE: The actual meter reading varies with the meter
used and the individual rectifier, bul, generally speaking,
the lower reading should be within '/; scale of zero ohms.
CAUTION: Be careful not to strike, scratch, or in any
other way damage the rectifier. Such damage may cause
the rectifier to short,

REGULATOR
When the field coil current is constant, the dynamo
oulpul vollage increases with an increase in engine rpm.

Field Coil Current, Dynamo Output gy)
Voltage/Engine rpm a
Dynamo Output Voltage

Field Coil Current

“Engine rpm
Regulator Operation at Low Engine Speed

Dynamo Rectifier

igen Ta a
‘tes
|

a a a — a

Green

Black

However, the voltage will become excessive at high
engine rpm, burning out the lights and overcharging the
battery unless the field current ts reduced at higher rpm.
Ihe regulator is included in the circuit to reduce the
field coil current al higher rpm, Keeping the voltage
belween |44~ 15 V for all electrical equipment as shown
in Fig, 547,

The regulator includes the armature, relay coil, re-
sistance (Rf), and three contact points (P,, Po, and P;).
Resistance Rf is in series with the field coil, while the
relay coil is connected to chassis ground. Point Pg» al
the end of the armature is the movable contact point,
which may be in contact with point P,, in contact with
no point, or in. contact with point P.

AL low rpm the dynamo outpul vollage magnetizes
the relay coil only slightly, and point Pg is held against
point P, by spring force, At this time the field coil
current, ly, flows through chassis ground ~ field coil
> terminal F + points P, and P, — terminal |. The
regulator circuit here has only negligible resistance to
current ly.

At moderate rpm the dynamo output voltage magnet-
izes the relay coil enough that it pulls point P, from
P,. At this time current |; flows through chassis ground
— field coil > terminal F ~ resistor Rf > terminal |.

Regulator Construction 548

|. Spring 2. Spring 3, Armature 4. Adjuster Arm
5, Point P,; 6, Point Py 7, Point Ps 8. Relay Coil

549

Regulator |

http://www.kz400.com MAINTENANCE 159

Regulator Operation at Moderate Engine Speed
Dynamo | Rectifier £50)

See

Green

rs." = |
Regulator , oT Ar
55))
LP
Armature =
——
De
a ei fe Ws
ts 3
Rie i —
“oj |
1 n ; |
a !
= — : _ /
Black =e
) Regulator =
The regulator circuit now provides resistance for current Regulator Controlled Dynamo Output Voltage
l;, reducing current |,. This reduces the dynamo output 552
voltage from what it would be otherwise, keeping it still =
between 14~15 V. Less than | V E
At high rpm the dynamo output voltage magnetizes IS'V
the relay coil sufficiently that it pulls point Pg in contact
with point P2. At this time no current flows to the field rt
coil, and the dynamo output depends on residual magnet- cs
ism in the rotor, Then, as the output voltage drops, oS
lhe relay coil loses its magnetism such that point Po a
separates from point P;, and current again flows to the 5
field coil. 2 Low Speed | | High Speed
Regulator testing
If the battery continually discharges or if it over-
charges, the regulator may be defective. Symptoms of | Engine rpm
excessive voltage are: (a) distilled water must be added
often to all battery cells and (b) lights burn out when ee 4 ies
running at high rpm. @Remove the left side cover and headlight unit (Pg. 92 ),
Check the battery before making the following test; and disconnect the 6P connector which is on the left

side of the motorcycle and the YP connector which is
in the headlight housing. This removes the load from
the dynamo,

charge the battery if it is less than 12 V. If the battery
is defective or discharged, the regulator will not function
properly.

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160 MAINTENANCE

Regulator Test

Black

@Set a multimeter to the 30 VDC range, and connect
the + meter lead to the battery + terminal and the —
- terminal.

meter lead to the battery

eStart the engine, hold the speed at 1,600 rpm, and note
the meter reading. The reading should be between
l4~ 15. V.

eGradually increase engine speed (do not decrease it
at any point), and check the meter reading when the
engine speed has reached 4,000 rpm. The reading
should be between 14~ 15 V.

NOTE: I! in the above test the engine speed is decreased

before the meter is read at 1,600 rpm or 4,000 rpm,

return the engine rpm to idling and then again gradually

increase the speed to 1,600 rpm or 4,000 rpm, Due to

hysteresis, there is a difference in the voltage depending

on whether the engine speed is increasing or decreasing.

Table 89 Regulator Resistance

Resistance

Terminal

+ Lead
> T Voltmeter
2'1oaq
!
a1 (°F)

Regulator

If the voltage was between 14~15 V in both checks,
the regulator is working satisfactorily. However, if the
voltage was not 14~ 15 V in either one of the tests,
carry out the following steps:

NOTE: The following steps are necessary only if regu-
lator operation is faulty. Do not otherwise open the
regulator cover If the motorcycle is still under
warranty, replace a faulty regulator; do not attempt
to open or adjust it,

eRemove the right side cover, and disconnect the regu-
lator leads, black, green, and brown, from the regulator
terminals marked E, F, and | respectively.

@®Remove the regulator cover.

@Set the multimeter to the Rxl or Rx1O range, and

measure the resistance in accordance with Table 89,

elf the points are fouled, clean them with clean paper
or cloth, using an ojl free solvent if necessary. lo

Remarks

OQ sf more than 0 22, points Po and P, are dirty or fouled.

"ye If no reading, resistor Rf is open. If no resistance, there
Position 2 about 9

is a short, is =
If no reading, the relay coil is open, If no resistance, there
is a short.

If more than 0 2, points Po and P, are dirty or fouled.

Position 1
Pasition 2

Points Po and P, are in contact by spring force.
Points P> and P are in contact by pressing on the armature with a finger.

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repair light damage, use emery cloth. If the points
cannot be repaired so that there will be zero ohms
resistance across them, replace the regulator for a new
one, Also, if the resistance Rf, relay coil, or any other
internal part is defective, replace the regulator with a

new one,

ePress down the armature, and inspect the armature gap
with a thickness gauge, The gap should be 0.3 mm or
more, If it is nol, correct it by bending the holder for
point P,,

®/nspect the gap between points P; and Po with a thick-
ness gauge. The gap should be 0.30~0.45 mm. If the
gap is incorrect, adjust it by bending the holder for
point P,,

Point + Holder

VY \

@®Replace the regulator cover, and reconnect the leads
(3) which were disconnected.

@Set the multimeter to the 30 VDC range, and connect
the meter + lead to the battery + terminal and the
meter — lead to the battery — terminal (Fig, 553),

MAINTENANCE 161

eStart the engine, and note the voltage at various engine
speeds,

@lurn off the ignition switch to stop the engine,

@|f the voltage was abnormal, either too high or too low,
adjust the regulator by bending the adjuster arm,
Bending the arm up increases voltage, and bending
the arm down decreases the voltage.

eStart the engine, and read the voltage with the engine
below 2.000 rpm. The reading should be 14~ 15 V.

®lurn off the ignition switch to stop the engine.

elf the vollage was too low, bend the adjuster arm up,
if the voltage was Loo high, bend the adjuster arm down,

eStart the engine, and read the vollage with the engine
at 4,000 rpm. The reading should be 14 ~ 15 V.

@lurn off the ignition switch to stop the engine,

elf the voltage was too low, bend the holder for point
P, down; if the voltage was too high, bend the holder
for point Ps up.

an ot |

Point\P; Holderggit ge” =
ee

i)

Decrease, Vol tage!

“* a

®Replace the regulator cover, and againcheck the voltage
with the engine below 2,000 rpm and at 4,000 rpm.
This recheck is necessary because the inner magnetic
field is influenced by the metal cover, possibly changing
regulator operation,

elf the voltage is still not correct, Continue adjusting
the regulator until the voltage is between J4~ 15 V.

BATTERY

The battery supplies the current to the starter motor
and serves as a back-up source of power to operate the
electrical equipment whenever the engine is turning over
too slowly for the dynamo to supply sufficient power,

162 MAINTENANCE

With proper care, the battery can be expected to
last a few years, but it may be completely ruined long
before that if it is mistreated, Following a few simple
rules will greatly extend the life of the battery.

1. When the level of the electrolyte in the battery is low,
add only distilled water to each cell until the level is
at the upper level line marked on the outside of the
battery. Ordinary tap water is not a substitute for
distilled water and will shorten the life of the battery.
Distilled water comes in a sealed, non-metallic con-
tainer; any other water is not distilled water.

2. Never add sulphuric acid solution to the battery.
This will make the electrolyte solution too strong
and will ruin the battery within a very short time.

3. Avoid quick-charging the battery. A quick-charge
will damage the battery plates.

4. Never let a good battery stand for more than 30 days
without giving it a supplemental charge, and never let
a discharged battery stand without charging it. If a
battery stands for any length of time, it slowly self-
discharges. Once it is discharged, the plates sulphate
(turn white), and the battery will no longer take a
charge.

5. Keep the battery well charged during cold weather
so that the electrolyte does not freeze and crack open
the battery. The more discharged the battery be-
comes, the more easily it freezes.

6. Always keep the battery vent hose free of obstruction,
and make sure it does not get pinched or crimped
shut. If battery gases cannot escape from this hose,
they will explode the battery.

7. Always remove the battery from the motorcycle for
charging it. If the battery is charged while still
installed, battery electrolyte may spill and corrode
the frame or other parts of the motorcycle.

8. DON'T INSTALL THE BATTERY BACKWARDS.
The negative side is grounded.

Electrolyte

The electrolyte is dilute sulphuric acid. The standard
specific gravity of the electrolyte used in warm climates
in a fully charged battery is 1.260 at 20°C (68°F),
In particularly cold regions a solution with a standard
specific gravity of 1.280 is used. The water in this
solution changes to a gaseous mixture due to chemical
action in the battery and escapes, which concentrates
the acid in a charged battery. Consequently, when the
level of the electrolyte becomes low, only distilled water
should be added. If sulphuric acid is added, the solution
will become too strong lor proper chemical action and
will damage the plates. Metal from the damaged plates
collects in the bottom of the battery. This sediment
will eventually cause an internal short circuit,

The specific gravity of the electrolyte is measured
with a hydrometer and is the most accurate indication
of the condition of the battery. When using the hydrom-
eter, read the electrolyte level al the bottom of the
meniscus (curved surface of the fluid). Fig. 562 shows
the relationship between the specific gravity of the
solution at 20°C (68°F) and the percentage of battery
charge. Since specific gravity varies with temperature,
and since the temperature of the solution being checked
is likely to be other than 20°C (68°F), the formula

Hydrometer

= = Electrolyte

|

given below should be used to compute what the
specific gravity would be if the temperature were 20°C
(68°F). When the temperature goes up, the specific
gravity goes down, and vice versa,
Celcius
$20=St+0,0007 (t—20)
Fahrenheit
Ses=St+0.0004 (t—68)
St=specific gravity at the present temperature
S20=specific gravity at 20°C
Ses=specific gravity at 68°F
l = present temperature of solution

Generally speaking, a battery should be charged if a
specific gravity reading shows it to be discharged to 50%
or less of full charge.

Specific Gravity/Battery Charge Relationship 662)

| Full Charge 1,28 (20°C)
1,20 1adh fsa Erte -— — oa

_
oi

opecific Gravity

&

Full Charge 1.26 (20°C) |

100] I

0 20 a0 60 80 100
Battery Charge %

Initial charge

New batteries for Kawasaki motorcycles are dry
charged and can be used directly after adding the
electrolyte. However, the effect of the dry charge
deteriorates somewhat during storage, especially if any
air has entered the battery from imperfect sealing.
Therefore, it is best to give the battery an initial charge
before using it in order to ensure long battery life.

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CAUTION: Because the battery gives off an explosive
gas mixture of hydrogen and oxygen, keep any sparks
or open flame away from the battery during charging.
ePour a 1.260 (specific gravity at 20°C or 68°F)
sulphuric acid solulion into each cell of the battery
up to the upper line,

eet the battery stand for 30 minutes, adding more acid
if the level drops during this time.

NOTES: |. If the temperature of the solution is over

30°C (85°F), cool the solution before pouring it into

the battery.

2. After pouring the acid into the battery, start charging

the battery within |2 hours,

®Leaving the caps off the cells, connect the battery to
a charger, set the charging rate at 1/10 the battery
capacity, and charge it for 10 hours. For example,
if the battery is rated at 12 AH, the charging rate
would be 1.2 ampere. If a constant voltage charger
is used, the voltage must be adjusted periodically to
keep the current at a constant value.

CAUTION: If the temperature of the electrolyte rises

above 45 C (115° F) during charging, reduce the charging

rate to bring down the temperature, and increase the
charging time proportionately.

@After charging, check the electrolyte level in each cell.
If the level has dropped, add distilled water to bring
it back to the upper line.

@Check the results of charging by measuring the speci-
fic gravity of each cell and by measuring battery voltage.
Battery voltage of a 12 volt battery directly after the
completion of charging should be 15 to 16 volts,

Ordinary charge

CAUTION: Because the battery gives off an explosive
gas mixture of hydrogen and oxygen, keep any sparks
or open flame away from the battery during charging.
eClean off the battery using a solution of baking soda
and water. Make especially sure that the terminals are
clean.
elf the electrolyte level is low in any cell, fill to over
the lower line but not up to the upper line since the
level rises during charging. Figure the charging rate
lo be between 1/10 and 3/10 of battery capacity.
For example, the maximum charging rate for a 12 AH
battery would be 3/10 x 12 which equals 3.6 amperes.
CAUTION: Charging the battery at a rate higher than
specified above could ruin the battery. Charging at a
higher rate causes excess heat, which can warp the plates
and cause internal shorting. Higher than normal

Table 90 Battery Troubleshooting Guide

Charging time (hours)=

MAINTENANCE 163

charging rates also cause the plates to shed active mate-

rial. Deposits will accumulate, and can cause internal

shorting.

®Measure the specific gravity of the electrolyte, and use
the graph, Fig. 562, to determine the percentage of
discharge. Multiply the capacity of the battery by the
percentage of discharge to find the amount of discharge
in ampere-hours, Use this figure in the formula below
lo compute charging time.

amount of discharge (AH)

charging current (A)

@®Remove the caps from all the cells, and begin charging
the battery at the rate just calculated, If a constant
voltage charger is used, the voltage will have to be
adjusted periodically to maintain charging current al
a constant value,

CAUTION: If the temperature of the electrolyte rises

above 45°C (115°F) during charging, reduce the charg-
ing rate to bring down the temperature, and increase

charging time proportionately.

eAlter charging, check the electrolyte level in each
cell. If the level has dropped, add distilled water to
bring it back up to the upper line,

®Check charging results by measuring the specific
gravity of each cell and by measuring battery voltage.
Battery voltage of a 12 volt battery directly after the
completion of charging should be 15 to 16 volts and
the specific gravity of the electrolyte should be more
than 1.250. If the voltage is lower than this, the
battery is not completely charged or can no longer take
a full charge. If the specific gravity of any one cell is
lower than 1.250, there may be damage in the cell.

xii

Test charging

When the battery is suspected of being defective,
first inspect the points noted in the chart below. The
battery can be tested by charging it by the ordinary
charge. If it will take a charge so thal the voltage and
specific gravily come up to normal, it may be considered
good except in the following cases:
* If the voltage suddenly jumps to over 13 volts just
after the start of charging, the plates are probably sul-
phated, A good battery will rise to 12 volts immediately
and then gradually go up to 12.5 ~ 13 volts in about
30 to 60 minutes after charging is started,
* If one cell produces no gas or has a very low specific
gravily, it is probably shorted,
* If there does not appear to be enough sediment to

Suspect Battery |
white (sulphated); + plates
broken or corroded

Replace
sediment up to plates,

al causing short
Voltage above 12 volts i

Good Battery |

(+) chocolate color
__(—) gray

Sediment none, or small amount

Plates

below 12 volts _ | Test charge
Electrolyte

= Fe | Fill and
level above plates below top of plates test charge

al below 1.100, or difference |
Test charge

above |.200 in all
cells; no two cells of more than 0.020 between
lwo cel Is |

more than 0.020 different,

Specific
gravily

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164 MAINTENANCE

short the plates, but one cell has a low specific gravity
after the battery is fully charged, the trouble may be just
that there is insufficient acid in that cell. In this case
only, sulphuric acid solution may be added to correct
the specific gravity.

* If a fully charged battery not in use loses its charge
after 2 to 7 days, or if the specific gravity drops mark-
edly, the battery is defective. The self-discharge rate
of a good battery is only about 1% per day.

IGNITION SYSTEM

The ignition system, shown in Fig. 563, consists of
the battery, contact breaker, condenser, ignition coil,
and two spark plugs (Pg. 166). The battery supplies
the current for the primary circuit, which includes the
contact breaker points, condenser, and the primary
winding of the ignition coil, When the points suddenly
open with the ignition switch turned on, a surge of
electrons is produced in the secondary circuit, which
includes the ignition coil secondary winding and the
two spark plugs. For this system lo function properly,
all ignition parts must be in good order, the ignition
liming correctly set, the ignition and engine stop switches
not shorted, and all wiring in good condition (no shorts
or breaks, and no loose or tarnished connections).

With the ignition switch on and the points closed,
current flows in the primary circuil, including the ig-
nition coil primary winding where the magnetic field
(which accompanies electron flow) is concentrated (due
to the winding). When the points open, this circuit
is broken stopping the electron flow and collapsing the
magnetic field. As this field collapses, magnetic flux
culs through the secondary winding inducing current
in the winding, The voltage of this current, dependent
on the number of turns in the secondary winding and
the speed of the drop in the primary winding voltage,
is much greater than the voltage in the primary winding.
lt is this high voltage thal causes a spark to jump
across the spark plug electrodes, Since a greater ratio
of secondary winding Lurns over primary winding turns
and a sharper drop of primary winding vollage increase
the secondary winding voltage that is produced, a certain
ratio of turns in the ignition coil has been chosen and
a certain vollage drop sharpness (determined by con-
denser and breaker point performance) has been designed
in the ignition system such that a spark of sufficient
bul not excessive strength will be produced.

Ordinarily in a 4-stroke engine, a spark jumps across
the spark plug electrodes only every other time that
the piston for that spark plug rises (once every 720°

Ignition Circuit

Ignition Switch

of crankshaft rotation) because between each com-
pression stroke, in which a fuel/air mixture ready for
combustion is in the cylinder, there is an exhaust stroke,
in which the piston rises only to push out the burned
gases. However, even if a spark does jump across the
electrodes during the exhaust stroke, there is no effect
since there is no compression and no fuel to burn.
Therefore, to eliminate any need for a distributor (thus
simplifying the system, making il more reliable), the
system is constructed so that both spark plugs fire every
time both pistons rise (once every 360° of crankshaft
rotation) although one piston is on the compression
stroke and the other on the exhaust stroke,

The contact breaker consists of one fixed and one
movable contact point. The movable point is pivoted,
and the heel on one end is held against the cam surface
on the timing advancer by a single leaf spring. As the
crankshaft rotates, the heel rides on the cam surface, and,
as the crankshaft reaches the position where ignition
takes place, the high spot on the cam surface pushes
out on the heel, which opens the points, As the heel
wears down, the point gap narrows, affecting ignition
timing. Consequently, the ignition timing must be
periodically adjusted to compensate for heel wear.

The condenser is connected in parallel across the
contact breaker points and serves to prevent current
from arcing across the points as they open, Arcing
across the points would reduce the sharpness of the
voltage drop in the primary winding, thus weakening
the spark plug spark, and also damage the surface of
the points. When the points are first opening, the
condenser absorbs a certain amount of current, giving
the points time to open far enough apart to where
current will not arc across, However, if the condenser
shorts, the current will simply flow through the con-
denser whenever the points open. When the condenser
is otherwise defective, the current will not be prevented
from arcing across the points at the time of ignition,
resulting in poor spark plug performance and burned
and pitted points,

Because the two spark plugs are connected in series,
the current through one spark plug must go also through
the other. Consequently, if a spark will nol jump across
the electrodes on one spark plug (due Lo dirty electrodes,
faulty plug lead, etc.), no spark will jump across the
electrodes on the other plug as well.

Contact breaker inspection
When the points become dirty, pitted, or burned, or
if the spring weakens, the points will not make the

Engine Stop Switch 663)

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contact necessary to produce a good spark, resulting
in unstable idling, misfiring, or the engine not running
al all. Inspect the contact breaker in accordance with
the periodic maintenance chart (Pg. 180), and repair
or replace if necessary.

Clean the points with clean paper or cloth or using
an oil-free solvent. A business card soaked in trichloro-
ethylene can be used lo remove traces of oil, To repair
light damage, use emery cloth or an oilstone. If the
points are badly worn down or damaged, or if the spring
is weak, replace the contact breaker,

Whenever the contact breaker is inspected or replaced,
apply a small amount of grease to the felt to lubricate
the cam in order to minimize wear of the contact
breaker heel, Be careful not to apply so much grease
that it can drop off or be thrown onto the points,
which will cause the points to foul and burn.
Condenser inspection

The condenser can usually be considered to be
Condenser Test

Capacitor Tester

Ignition Coil Test

Electro-Tester

MAINTENANCE 165

defective if a long spark is seen arcing across the points
as they open or if the points are burned or pitted for
no apparent reason, Replace the condenser any time
it appears defective and whenever the contact breaker
is replaced,

NOTE: For checking with a capacitor tester, condenser
specifications are: 0,22+0,02yfd., 1,000 WVDC,

Ignition coil inspection

The most accurate test for determining the condition
of the ignition coil is made with the Kawasaki electro-
tester, The ignition coil must be connected to the tester
in accordance Lo the tester directions and should produce
at least a 5 mm spark, Since an electrotester other than
the Kawasaki electrotester may produce a different arcing
distance, the Kawasaki electrotester is recommended for
a reliable result,

If an electrotester is not available, the coil can be
checked for a broken or a badly shorted winding with
an ohmmeter, However, an ohmmeter cannot detect
layer shorts and shorts resulting from insulation break-
down under high voltage.

To measure the primary winding resistance, set the
ohmmeter to the Rx 1 range, and connect one ohmmeter
lead to the red/yellow lead and the other to the blue
lead from the ignition coil. The resistance should be
3.2~4.8 2. To measure the secondary winding resis-
tance, set the ohmmeter to the R x 100 range, and con-
nect one ohmmeter lead to one of the spark plug leads
and the other ohmmeter lead to the remaining spark plug
lead. The resistance should be about 10.4~15.6 KQ.

Ignition
Coil

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166 MAINTENANCE

T Fes
ji 1

If the coil does not produce an adequate spark, or
if either the primary or secondary winding does not
have the correct resistance, replace the ignition coil.

Check with the highest ohmmeter range for conti-
nuity between the red/yellow lead and the coil core and
between the plug leads and the coil core. If there is
any reading, the coil is shorted and must be replaced.
Also, replace the ignition coil if either spark plug lead
shows visible damage.

TIMING ADVANCER

The timing advancer is a device that advances the
ignition timing (makes the spark plugs fire sooner) as
engine rpm rises, It consists of two weights and two
springs connected to the timing cam that opens the
contact breaker points, The more that the engine speed
rises, the more that the weights are thrown out against
spring tension, turning the cam in the direction of crank-
shaft rotation and causing the points to open sooner.

If the mechanism is damaged, has weak or broken
spring(s), or does not move smoothly, the ignition timing
will not advance smoothly or it may stick in one position,
This will result in incorrect timing at certain engine
specds, causing poor engine performance. Failure to
advance at all will cause poor high speed performance,
and excessive advance will cause knocking and poor low
speea performance,

Ignition Timing/Engine rpm Relationship 668)
BTDC
40° -}——40°

f 96704190

eel a]
mit |
<
= A 21 00#200
20
5 |
‘= +200

10

0 1000 ©2000) =63000 )§=64000 © 5000
Engine rpm
Inspection and lubrication
Remove the timing advancer (Pg, 48 ), and check
that the mechanism moves smoothly by hand and that
no parts are visually worn or damaged. Wipe the ad-
vancer clean, apply oil to it, and fill the groove in the
advancer body with grease in accordance with the peri-
odic maintenance chart (Pg. 180).

Replace the advancer (Pg. 49 ), adjust the timing
(Pg. 12), and check it with a strobe light for both
low and high speed operation (Pg. 13 ). If the timing
differs from that which is shown in the graph (Fig. 568),
replace the timing advancer with a new one.

SPARK PLUGS

The spark plugs ignite the fuel/air mixture in the
combustion chambers. To do this effectively and at the
proper time, the correct spark plugs must be used, and
the spark plugs must be kept clean and adjusted.

) 1

Spark Plug

a aaa

—(4 l. Terminal
48) 2. Cement

Reach 3. Wire Ring
6) 4, Gasket

5, Insulator
= rr 6. Center Electrode
0.7~O0.8 mm 7. Side Electrode

Tests have shown the NGK B-8ES or ND W24ES
set to a 0.7 ~0.8 mm gap to be the best plug for general
use. But since spark plug requirements change with
ignition and carburetion adjustments and with riding
conditions, this plug may have to be replaced with one
of the next higher or lower heat range. Whether or not
a spark plug of a different heat range should be used
is generally determined upon removing and inspecting
the plug.

When a plug of the correct heat range is being used,
the electrodes will stay hot enough to keep all the
carbon burned off but cool enough to keep from damag-
ing the engine and the plug itself. This temperature is
about 400 ~ 800°C (750 ~ 1450°F) and can be judged
by noting the condition and color of the ceramic insu-
lator around the center electrode, If the ceramic is
clean and of a light brown color, the plug is burning
at the right temperature,

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Spark Plug Condition

Carbon Fouling Oil Fouling

A spark plug for higher operating temperatures is
used for racing and other high speed applications. Such
a plug is designed for better cooling efficiency so that
it will not overheat and thus is often called a “colder”
plug. If a spark plug with too high a heat range is used—
that is, a “cold” plug that cools itself too well—the plug
will stay too cool] to burn off the carbon, and the carbon
will collect on the electrodes and the ceramic insulator,
If enough of this carbon collects, it may prevent a spark
from jumping across the gap, or it may short the spark
out by bridging across the electrodes or by conducting
along the outside of the ceramic, Carbon build-up on
the plug can also cause the electrodes to heat up red-hot,
which will cause preignition, indicated by knocking,
which in turn may eventually burn a hole in the top of
the piston,

A spark plug in the lower heat range is used when
engine temperature is comparatively low such as for
constant city Use or during the break-in period when
the motorcycle is not operated at high speed. Such
a plug is designed to hold the heat and thus is often
referred to as a “hotter” plug. If a “hot” plug is used
for racing or other high speed use, the plug will be too
hot, causing engine overheating and preignition.
Inspection and replacement

Remove cach plug and inspect the ceramic insulator.

If the insulator is clean and has a light brown color,
the correct plug is being used, If it is fouled black,
change Lo the “hotter” NGK B-7ES, If the ceramic is
burned while and the electrodes are burned, replace the
plug with the “colder” NGK B-9ES, However, if the
spark plug still fouls or overheats after changing to a
hotter or colder plug, the cause of the trouble may be
other than the spark plug such as faulty carburetion or
ignition timing.
CAUTION: When the type of riding changes—for exam-
ple, a change to faster riding after the break-in period is
over—the spark plugs should be inspected and changed
if necessary. The NGK B-7ES plug in particular can
damage the engine if used for high speed riding.

Clean the electrodes and the ceramic insulator around

the center electrode by scraping off any deposits and
cleaning the plug in a high flash point solvent of some
kind. If the gap has widened, reset it to the standard
0.7 ~ 0.8 mm gap. If the electrodes are badly worn
down or burned, replace the plug. A plug must also
be replaced any time there is visible damage such as
cracked ceramic or damaged threads,
NOTE: If the spark plugs are replaced by any other
than the recommended NGK B-7ES, B-8ES (standard)
or B-9ES, make sure that the replacement plugs have
the same:

Normal Operation

Overheating

(1) thread pitch
(2) reach (length of threaded portion must be
19 mm)
(3) diameter (diameter at threads must be 14 mm)
(4) electrode configulation (standard, not projected
insulator or racing)
Plug Reach
Correct reach 4

B-8ES

Too short
B-8HS

Carbon i4mm |
builds up here

lf a plug with the wrong thread pitch or thread
diameter is used, the cylinder head will be damaged. Ifa
plug with too long or short a reach is used, carbon will
build up around the plug or plug hole threads, possibly
causing engine damage and making the old plug difficult
Lo remove or the new one difficult to install,

STARTER MOTOR CIRCUIT (Only on KZ400D)
The starter motor circuit includes the starter button
(switch), starter relay, battery, and starter motor, When
the ignition switch is on and the starter button is pushed,
a small amount of current flows through the switch and
the relay coil, This current magnetizes the relay core,
which then pulls the armature to it, closing the relay
contacts, The closed contacts complete a circuit for
the starter motor, and the motor turns. The reason for
using a relay instead of using the switch to turn on the
starter motor directly is that the starter motor requires
much current — enough that relatively thick wire is
necessary to carry the current to the starter motor,
Because it is not practical to put a heavy switch on the
handlebar and have large wires running to it, the
starter switch is made to carry just the light relay coil
current, and heavy contacts inside the relay carry the
starter motor current.
NOTE: Because of the large amount of current, never
keep the starter button pushed any time that the starter
motor will not turn over, or the current may burn out
the starter motor windings.

The starter motor is installed with a sprocket and
chain arrangement to transmit starter motor rotation to
the crankshaft, In place of the solenoid used in auto-
mobiles, a clutch (Pg. 170) disengages the starter motor
once the engine starts.

MAINTENANCE 167

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168 MAINTENANCE

Starter Motor Circuit

Starter Motor

Fig. 575 shows starter motor construction, The field
coils are wound around four cores, forming the yoke,
and the armature windings are connected to the com-
mutator and receive their current through the brushes.
If the brushes are not making good contact, no starter
motor current will flow at all since the field coils and
armature windings are connected in series, and the motor
will not turn over, A short or open in a coil or winding
may also cause the motor to be inoperative. Particles
from brush wear may be another cause of starter motor
failure; these particles may get onto the bearing at the
rear of the motor, causing heat seizure.

Gears are provided at the output side of the starter
motor, These gears reduce the rotational speed of the
armature Lo give more power to the output shaft,

Carbon brushes

Worn brushes or weak springs will cause poor brush
contact,

Measure the length of the brushes, and replace both
if either one is worn down to less than the service limil,

Table 91 Starter Motor Brush Length

Service Limit

__11.0*12.5 mm

Starter Motor Construction

OOM ®9

ys, a i= a
OQ@® @6®@
| |

ee ee ——“_‘i_—R “CL

Battery

Se a =

A, CGu-— ]
We | all i

=
wil Starter Button

S *

Ignition switch Engine Stop Switch

Carbon Brushes

Spring tension should be 495~605 grams but a spring
can be considered serviceable if it will snap the brush
firmly into place.

Commu tator

A dirty or damaged commutator will result in poor
brush contact and cause the brushes to wear down
quickly. In addition, particles from brush wear accum-
mulaling between commutator segments may cause
partial shorts,

Correct the commutator surface if necessary with
fine emery cloth, and clean out the grooves as illus-
trated, Determine as accurately as possible the depth

DZ dy a3 15)

|. Shaft
2, Sprocket

3. O Ring

4. Grease Seal

5. Gears

6. End Plate

7. Field Coil

&. Armature

9. Armature Winding
10. Cores

Il. O Ring

12. Brush Plate

I3. Spring

I4. Brushes

a /. 15. Commutator

lé. End Cover

16) 17. Yoke Assembly
18, End Cover
19. Screws

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of the grooves between commutator segments. Replace
the armature with a new one if the groove depth is less
than the service limit.

Commutator ‘)

Segment —
Bad =

Table 92 Commutator Groove Depth

| 0.5~0.8 mm

Using the R x | ohmmeter range, measure the re-
sistance between each two commutator segments, If
there is a high resistance or no reading between any
two segments, a winding is open and the armature must
be replaced,

Service Limit
0.2 mm

Using the highest ohmmeter range, measure the re-
sistance between the commutator and the shaft, If
there is any reading at all, the armature has a short
and must be replaced,

MAINTENANCE 169

Even if the foregoing checks show the armature to
be good, it may be defective in some manner not readily
detectable with an ohmmeter, If all other starter motor
and starter motor circuit components check good, but
the starter motor still does not turn over or only turns
over weakly, replace the armature with a new one,

Field coils

Using the R x 1 ohmmeter range, measure the re-
sistance between the + side carbon brush and the starter
motor lead. If there is not close to zero ohms, the
field coils have an open and the yoke assembly must
be replaced.

Field Coil Test Ohmmeter stl)

Using the highest ohmmeter range, measure the re-
sistance between the + side carbon brush and the yoke
(housing). If there is any meter reading, the coils are
shorted to ground and the yoke assembly must be
replaced,

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170 MAINTENANCE

Starter Relay Contact Test

Starter

Starter Motor Lead
Be,

Ohmmeter
Starter relay

Disconnect the starter motor lead from the starter
relay, and connect an ohmmeter set to the R x | range
across the relay terminals, Push the starter button, and
see if the meter reads zero ohms. If the relay makes a
single clicking sound and the meter reads zero, the relay
is good, If the relay clicks but the meter does not read
zero, the relay is defective and must be replaced,

If the relay does not click at all, disconnect the other
two leads (black and yellow/red), and measure the re-
sistance across them. If the resistance: is not close to
vero ohms, the relay is defective.

éa

, We. GStaneriRetay
. aia

However, if there is zero ohms resistance, the relay
may be good; check that there is actually voltage to the
relay before deciding that the relay is defective, To
check for the voltage, first turn the meter to 30 VDC,
connect the — meter lead to the yellow/red lead which
was disconnected [rom the relay, and connect the +
meter lead to the black lead. When the starter button
is pushed, the meter should read battery voltage, If it
does not, there is wiring trouble. If the meter reads
battery voltage but the relay does not click, the relay
is defective.

Red/ Yellow
Starter Button

——
=

Battery

STARTER MOTOR CLUTCH, CHAIN
(Only on KZ400D)

Fig. 585 shows starter motor clutch construction, Ihe
clutch body is fixed to the crankshaft through the
rotor. When the starter clutch sprocket rotates in the
direction of the arrow, each of the three rollers is
wedged into the more narrow space between the clutch
body and the starter clutch sprocket hub (the portion
jutting out from the sprocket), thereby locking the clutch
body and starter clutch sprocket together. With these
two locked, starter motor rotation is transmitted to the
crankshaft through the starter chain, starter clutch
sprocket, rollers, clutch body, and rotor,

When the engine starts, at first friction with the
starter clutch sprocket (and at higher speeds, inertia)
moves the rollers back against the tension of their springs
so that they no longer serve as wedges locking the clutch
body and starter clutch sprocket together. In this
manner, the engine rotates freely without forcing the
slarter motor to turn with it.

as,

Starter Motor Clutch 585)

l. Sprocket 4,
2. Starter Clutch 5. Spring

Spring Cap

3. Roller 6 Crankshaft

lf the rollers or the starter clutch sprocket hub
becomes damaged or worn, the rollers may lock in

place so that the starter motor will not disengage when
the engine starts. On the other hand, roller or sprocket
hub damage could prevent the clutch from engaging
properly, causing the starter motor to run freely without
transmitting the rotation to the crankshaft or to make
noise while Lransmitting rotation,
Clutch inspection

Remove the dynamo cover, and turn the rotor by
hand, When turning the rotor counterclockwise, the
starter clutch sprocket should turn with the rotor, but,
when turning the rotor clockwise; the sprocket should
not turn, If the clutch does not operate as it should
or if it makes noise, disassemble the starter motor clutch
(Pg. 45), examine each part visually, and replace any
worn or damaged parts.

i

: _—— = —— “a
Starter chain inspectio

Remove the starter chain (Pg. 46 ), hold the chain.

laut with a force of about 5 kg in some manner such as
the one shown in Fig. 587, and measure a 20-link length.
Since the chain may wear unevenly, take measurements
at several places. If any measurement exceeds the

service limit, replace the chain.

Service Limit

155.5 mm 157.8 mm

IGNITION SWITCH

The ignition switch has three positions: off, on, and
park, In the off position, all circuits are turned off and
the key can be removed from the switch. In the on
position, the motorcycle can be started, all electrical
equipment can be used, the headlight, tail light, and
meter illuminating lights are lil, and the key is held in

MAINTENANCE 171

the switch so that it can not be removed. In the park
position, the tail light goes on so that the motorcycle
can be more safely stopped along the road at night,
all other electrical circuits are cut off, and the key can
be removed from the switch.

Testing the switch

Table 94 shows the internal connections of the
ignition switch for each switch position. To check the
switch, disconnect the lead plug from the switch, and
use an ohmmeter to verify that there is continuity (zero
ohms) between all the connections that are listed in the
table for each switch position, and that there is no conti-
nuity between the leads that are not connected. If the
switch has an open or short, replace the switch with a

new one,

Table 94 Ignition Switch Connections

LEAD = bei

HEADLIGHT CIRCUIT

The headlight circuit is shown in Fig. 590. When
the ignition switch is turned on, the headlight circuit
is completed, turning on the headlight, tail light, and
meter illumination lights. The dimmer switch is used
to select high or low beam, When the headlight is on
high beam, the high beam indicator light is also lit,

A headlight switch is provided on the European model.
The center PO position of the headlight switch turns on
the city light and the tail light for driving in the city
after dark. When the switch is turned to the ON position,
the city light stays on even though the headlight is lit too,
High or low beam can be selected only when the headlight
switch is in the ON position. There is also a PASS po-
sition of the horn/passing button, This position is spring
loaded, and can be used to turn on the passing beam
whether the headlight is turned on or not. When the
button is pushed to PASS, the headlight high beam
(passing beam) comes on to signal the driver of the
vehicle ahead that you are about to pass him. The
passing beam goes off as soon as the button is released,

172 MAINTENANCE

Headlight Circuit

Hom/Passing Dimmer

Switch Switch
eee oe ee Hi Lo

Headlight |
City Light

High Beam
Indicator Light

Ignition Switch

The same bulb is used for both the tail light and the
brake light, but the bulb has a separate filament for each
light. The tail light filament is controlled by the headlight
circuit. The brake light filament is controlled by the
brake light circuit, which is explained in the following
section.

Headlight trouble

If the headlight does not light, check to see if the
bulb has burned out. If the bulb has burned out, the
sealed beam unit must be repalced. On the European
model the headlight bulb or city light can be replaced
separately as the headlight is of semi-sealed construction.
If the bulb is good, check the dimmer switch and the
headlight siwtch. Tables 95 and 96 show the connections
in the dimmer switch for both high and low beam, and
the connections in the headlightswitch. Disconnect the
leads to the dimmer switch or headlight switch, and use
an ohmmeter to see that only the connections shown
in the table have continuity (zero ohms). If the
switch has an open or a short, it can be disassembled
for repair, The contact surfaces may be cleaned, but
no internal parts are available for replacement. If any
parts are not repairable, the switch must be replaced as
a unit, However, if the dimmer switch or headlight
switch is good, check the ignition switch, the wiring,
and the dynamo,

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Headlight
Switch

—- === US model
jist, EUPOpean model
6P Bi
al. ea =
Brake /Tail
Light

Table 95 Dimmer Switch Connections

_High Beam

Table 96 Headlight Switch Connections

| (Only on European model)
Color

Switch Je Passing:

If the headlight lights but does not light brightly,
the trouble may be that the headlight is of improper
wallage or that the dynamo is not supplying sufficient
current. However, the trouble may also be caused by a
short or a component drawing too much current in some
other part of the electrical system.

Tail light trouble

If the tail light does not go on when the ignition
switch is turned on (or for the European model when
the ignition switch is turned on and the headlight switch
is turned Lo PO position), the filament is probably burned
out, However, if the bulb is good, check the wiring,
ignition switch, headlight switch, fuse and battery.

BRAKE LIGHT CIRCUIT

The brake light circuit is shown in Fig. 594. When
the ignition switch is turned on, the brake light goes
on whenever the circuit is closed by either the front
or rear brake light switch. The same bulb is used for
both the brake and tail lights as explained in the
preceding section.

The KZ400S front brake light switch is mounted on
the front brake lever body and operated mechanically
when the brake lever is pulled. The KZ400D has a
pressure switch installed in the brake fluid line, and is
operated by fluid pressure when the brake lever is pulled.
The front brake switches never require adjustment and
so are not designed to be adjusted. They can not be
disassembled for repair and must be replaced when
defective,

The rear brake light switch for both models is a
plunger type switch actuated by a spring attached to
the rear brake pedal, It can be adjusted by changing
its position higher or lower in the mounting bracket
(See Pg, 20).

The brake light failure indicator switch is in the brake
light circuit as a warning device to indicate during vehicle
operation whether or not the brake light is functioning
properly, Brake light failure may be due to a burned
out bulb or some other failure in the brake light circuit.
Brake light circuit trouble

Brake light circuit inspection involves the front brake
light switch, rear brake light switch, brake light, brake
light failure indicator switch, brake light failure indicator
light, and wiring.

Front Brake

Brake Light Circuit Light Switch

Battery =

Black/¥ ellow

Brown

Brake Light Failure
Indicator Light

Brown Brown Brown

MAINTENANCE 173

(1) Front brake light switch inspection

@Disconnect the front brake light switch leads.

@Set an ohmmeter to the R x | range, connect the meter
to the switch terminals (KZ400D) or switch leads
(KZ400S), and determine whether or not there is
continuity whenever the front brake lever is squeezed.
If there is no continuity, replace the switch.

K2Z400D

K2Z400S
iy

Brake Light
-_{ Switch Leads

*
7)

Te

NOTE (when the front brake light switch is replaced
with a new one):

|. If brake fluid spills when the switch is replaced,

painted or chromed surfaces may become damaged.

Rear Brake

Light Switch xy)

Blue

Brake/Tail
Blue Sidi

Black/¥ ellow

Blue - —=->
Black/Yellow _ =—
: :
Green! While

Brake Light Failure
Indicator Swilch

Hlue

CK

=a a:
LJ} Red

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174 MAINTENANCE

If any fluid spills on the fender or elsewhere, wipe
iL up immediately.

2. Apply a small amount of a non-permanent locking
agent such as Kawasaki Liquid Lock-K to the switch
threads before mounting the switch. However, so
that no Lock-K will get mixed in with the brake
fluid, do not apply any on the lower fourth of the
ihreads,

3. After the switch has been installed, air bleed the
front brake lines,

(\!] Rear brake light switch inspection

eDisconnect the rear brake light switch leads,

@|nspect in the same way thal the front brake light

switch was inspected. If there is no continuity when-

ever the rear brake pedal is depressed, replace the
switch.

(1) Brake light failure indicator switch inspection

@lurn on the ignition switch, and apply the brakes,
At this time the indicator light sho',d go on,

eWith the brake applied, remove the brake light bulb,
At this time the indicator light should still be lit,
eWith the brake applied and the bulb removed as in
the previous step, release the brake, The indicator light
should flash at a rate of 7O~170 times a minute,

If the above conditions are met, the brake light failure
indicator switch is functioning properly,

SipGrake LightFailure
‘7 23 “indicatorsighthes
al — +
= A : : se - —,

—_—_—_—_———

ew a bd ay
1 a)
oe

ZABrake Light ailurelindicator Switch

Table 98 Indicator Light Demehen

All Normal
Brake Being Applied ,

Brake L. ight Burned Out

AE NOE a: a | ok
Brake Not Applied : ie

Brake Light Burned Out

Brake eae Lint Indicator a

[IV] Brake light circuit inspection

(in all the measurements the — meter lead goes to chassis
ground)

(1) Even though the brake light lights, the indicator

light does not go on:

@®Mcasure battery vollage.

®Jurn on the ignition switch.

e@Set a volimeter to the 30 VDC range, and connect
the meter to the blue indicator switch lead and to
ground without disconnecting the indicator switch,
If the voltage is less than battery voltage, the wiring is
defective,

@Measure the voltage between the green/ white indicator
switch lead and ground, If the voltage ts less than
battery voltage, the indicator light is burned out; if the
voltage is the same as battery voltage, the indicator
switch is defective.

(2) The brake light is burned out, and, with neither

brake applied, the indicator light doesn’t flash:

ad, the indicator light lights without flashing

@Measure battery vollage,

®7urn on the ignition switch.

@Set a voltmeter to the 30 VDC range, and measure the
voltage between the blue indicator switch lead and
ground. I! the voltage is less than battery voltage, the
indicator switch is defective; if the voltage is the same
as the battery voltage, either the front or the rear
brake light switch is defective.

b. the indicator light does not light

e@Neasure battery voltage.

®lurn on the ignition switch.

eSet a volimeter to the 30 VDC range, and measure
the voltage between the green/white indicator switch
lead and ground. If the voltage is less than battery
voltage, the indicator light is burned out; if the voltage
is the same as battery voltage, the indicator switch is
defective,

(3) Although the brake light is not burned out, the

indicator light either lights even when neither brake
is Being applied or flashes:

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a. the indicator light does not go off when the brake is

released

eif the brake light also won't go off when the brake is
released, the brake light switch is defective; if it doesn’t
light, the indicator switch is defective,

b. the indicator light flashes

@Measure the battery voltage.

®lurn on the ignition switch.

*Set a voltmeter to the 30 VDC range, and connect
the meter to the blue indicator switch lead and to
ground. Apply one of the brakes, and note the voltage.
If the voltage is less than battery voltage, the wiring is
defective; if the voltage is the same as battery voltage,
the indicator switch is defective.

TURN SIGNALS

A wirtng diagram of the turn signal circuit is shown
in Fig. 569. When the ignition switch is on and the
turn signal switch is turned to R or L, a ground is
provided for the circuit so current can flow. Current
to the right or left turn signals flaws through the closed
contacts and the resistance wire inside the turn signal
relay, and the turn signals go on, The resistance wire
quickly heats up, expands, and allows a spring to pull
the contacts open. When the contacts have opened,
lhe circuit is broken, the turn signals go off, and the
resistance wire cools and contracts, closing the contacts
so that the cycle can begin again. The indicator light
in the tum signal circuit flashes on and off with the
lurn signals to indicate that they are working properly.

Since the turn signal relay is designed to operate
correctly only when two turn signals (one front and one
rear) and the turn signal indicator light are properly
connected in the circuit, trouble may result from a
burned out bulb, a bulb of incorrect wattage, loose
wiring, as well as from a defect in the relay itself, In
general, if the trouble with the circuit is common to
both right and left turn signals, it is probably caused
by a defective turn signal relay, although it may be due

Turn Signal Circuit

L White Fuse
Blac k —_ lo ;
+ ia
Battery a
Brown
Resistance Wire
Contacts —————

MAINTENANCE 175

to a bad switch, wiring, or battery. If the trouble is
with only one side—either right or left—then the relay is
not at fault since the same relay is used for both sides.

Turn signal trouble
(1)Neither right nor left turn signals come on at all:
@Check that battery voltage is normal.
eUnplug the relay leads and use an ohmmeter to
check thal there is continuity (close to zero ohms)
between the relay terminals. If there is no ohm-
meter reading, or if there is several ohms resistance,
replace the relay with anew one.

a = a .
iurntsignaliRela
a

i
.: i

-| a a,

elf the relay checks good, turn the meter to the
30 VDC range, connect the + meter lead to the
brown lead thal was disconnected from the relay,
and connect the — meter lead to the orange lead.
With the ignition switch on, first switch the turn
signal switch to the R and then to the L position,
The meter should register battery voltage al either
position, If it does not, the fuse, ignition switch,
or wiring ts al fault. If battery voltage ts read on
the meter but the turn signals will still not work
when the relay is reconnected, then recheck all wir-
ing connections,

Orange 599
c |L Turn Signal Switch
3 Io a Signal Swite
i |
Slate
Seep
in|
Slate
Green

Turn Signal
Light

ee)
ei Fy #4

, Orange
54 0 TT aE fi

Plate

8
©
(3)

Ss
2
=

Turn Signal Indicator Light

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176 MAINTENANCE

Pi

Bro inilfead ¢

\" Orange

== _——

J co = = =

(2)Both right or both left turn signals come on and
stay on or flash too slowly:
@Check that battery voltage is not low.
@Check that all wiring connections are good,
@Check that the turn signal bulbs and indicator bulb
are of the correct wattage,
elf all of the above check good, replace the relay.
(3)A single light on one side comes on and slays on:
either the light that does not come on is burned
out or of the incorrect waltage, or the wiring Is
broken or improperly connected.
(4)Neither light on one side comes on:
@Uniless both lights for that side are burned out, the
trouble is with the turn signal switch,
(5)Flashing rate is loo fast:
e/f this occurs on both the right and left sides, check
that the battery is not being overcharged (indicating
a defective regulator). If the dynamo and the battery
voltage are normal, replace the turn signal relay,
elf this occurs on only one side, one or both of the
turn signal bulbs are of too high a wattage.

HORN

[he horn circuit and construction are shown in
Fig. 601. When the horn button is pressed with the
ignition switch on, the horn is grounded to complete
the horn circuit, Current then flows through the horn
contacts and horn coil, magnetizing the iron core, The
magnetized iron core pulls on the armature and dia-
phragm assembly, the movement of which pushes open
the contacts, interrupting the current flow, Since the
core now loses ils magnetism, the armature and dia-
phragm assembly springs back to its original position,
closing the contacts, This cycle repeats until the horn
button is released, Since each cycle takes only a
fraction of a second, the diaphragm moves fast enough
lo produce sound,

Horn Construction —_
Adjusting

Screw Core

——,_ Contacts ore

Diaphragm \

Horn Button

The contacts wear down after long use, requiring
adjustment from time to time (Pg. 22). If the horn
itself is determined to be at fault and adjustment fails
to correct the trouble, the contacts or some other
component in the horn is defective. The horn cannot
be disassembled and must be replaced if defective.
Horn trouble

eCheck that battery voltage is normal,

@Disconnect the leads to the horn, and connect to the
horn leads a multimeter set to the R x | range
to check for continuity (close to zero ohms). If the
reading is several Ohms or if there is no reading al all,
replace the horn,

elf the reading is very close to zero, set the multimeter
to the 30 VDC range, and connect the meter to the
leads that were disconnected from the horn, The +
meter lead goes to the brown lead, and the — meter
lead goes to the black lead. With the ignition switch
on, press the horn button, The meter should register
battery voltage. If it does not, the fuse, ignition
switch, horn button, or the wiring is at fault.
elf the meter does show battery voltage, indicating that
the horn trouble lies within the horn itself, and adjust-
ment fails to correct the trouble, replace the horn,

NOTE: Do not loosen the armature mounting since
doing so would alter the armature position such that the
horn would probably have to be replaced.

SPEEDOMETER, TACHOMETER

The speedometer and the tachometer are sealed units
which cannot be disassembled, If either fails to work
satisfactorily, it must be replaced as a complete unit,

The speedometer and tachometer illumination lights
and the indicator lights are independent and can be re-
moved for replacement if necessary.

SPECIAL TOOLS

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Appendix

APPENDIX 177

TOOL NO,
57001-101
§7001-102
57001-360
57001-361
57001-106
§7001-162
56019-111
5/001-132
57001-137
57001 -294
5/001-139
56019-040
5/001-380
5/7001-110
57001-163
57001-288
§7001-289
57001-290
§7001-138
57001-285

DESCRIPTION

VALVE SEAT CUTTER 30°

VALVE SEAT CUTTER 45°

INLET VALVE SEAT CUTTER 75°
EXHAUST VALVE SEAT CUTTER 75°
VALVE SEAT CUTTER HOLDER
VALVE GUIDE REAMER

MASTER CYLINDER STOPPER REMOVER
MASTER CYLINDER RING DRIVER
STEM BEARING DRIVER

STEM BEARING DRIVER ADAPTER
BEARING DRIVER HOLDER
ENGINE SPROCKET HOLDER
TRANSMISSION CIRCLIP DRIVER
SPARK PLUG WRENCH

VALVE GUIDE ARBOR

WHEEL BEARING DRIVER “A”
WHEEL BEARING DRIVER “B”
WHEEL BEARING DRIVER “"C”
STEM CUP DRIVER

SHIFT DRUM BEARING DRIVER

178 APPENDIX

TOOL NO.

97001-134
57001-179
57001-1861
57001-370
57001-371
57001-372
57001-115
57001-158
57001-166
57001-241
57001-242
57001-244
57001-167
57001-191
57001 -254
57001-255
57001-7165

http://www.kz400.com

DESCRIPTION

STEM NUT WRENCH

FRONT FORK CYLINDER HOLDER ASSEMBLY
FRONT FORK CYLINDER HOLDER ADAPTER
CYLINDER HEAD BOLT WRENCH HANDLE
CYLINDER HEAD BOLT WRENCH SOCKET 10 mm
CYLINDER HEAD BOLT WRENCH SOCKET 13 mm
PISTON RING PLIERS

STEM BEARING PULLER

STEM BEARING ADAPTER

VALVE SPRING COMPRESSOR ASSEMBLY
VALVE SPRING COMPRESSOR ADAPTER

VALVE SPRING COMPRESSOR CENTER SHAFT
BALANCE ADJUSTER

FRONT FORK OIL SEAL DRIVER

DYNAMO ROTOR PULLER

DYNAMO ROTOR HOLDER

CYLINDER HEAD HOLDING PLATE

REF.NO.
38
39
40
41
42
43
44
45
46
47
48
49
50
51

LGR

http://www.kz400.com

TOOL NO.

57001-127
57001-401
57001-400
57001-123
57001-350
57001-164
57001-910
57001-912
57001-913
57001-914
57001-265
57001-264
57001-340
57001-921
57001-208
97001-226
57001-154

APPENDIX 179

DESCRIPTION

VACUUM GAUGE

VACUUM GAUGE ADAPTER

OIL PRESSURE GAUGE ADAPTER

COMPRESSION GAUGE

VALVE CLEARANCE ADJUSTER

OIL PRESSURE GAUGE

PISTON PIN PULLER ASSEMBLY
ADAPTER “A” — Not used for KZ400
ADAPTER “B”
ADAPTER “C" — Not used for KZ400

KICK SHAFT OIL SEAL GUIDE

SHIFT SHAFT OIL SEAL GUIDE

PISTON BASE

PISTON RING COMPRESSOR ASSEMBLY

FUEL LEVEL GAUGE

VACUUM GAUGE

RETAINING RING PLIERS

http://www.kz400.com

180 APPENDIX
PERIODIC MAINTENANCE CHART

After | After
initial initial

Every Every
subsequent | subsequent |

Frequency

Operation

Check spoke tightness and rim runout

_ e

Clean, set spark plug gaps

15

Check, adjust points, timing

Check valve clearance

Tighten bolts and nuts

: we

int |

[Check drivechain weer |
=

a

ties

ee
| Clean air cleaner element 7 . | 101 |
Perform general lubrication j in 181

Change engine oil

Every subsequent 3,000 km

a Every subsequent 6,000 km

Change oil filter element

| 132
Every 300km

| Check, adjust drive chain

Every 800 km

Every 10,000 km _

| Change brake fluid *Every year or 10,000 km _
Regrease wheel bearings | “Every 2 years or 20,000 km

is

166

="
©

= | eee

Regrease speedometer gear housing

*Every 2 years or 20,000 km

Regrease brake camshaft *Every 2 years or 20,000 km

—

4

a |

Lubricate steering stem bearings *Every 2 years or 20,000 km

* Whichever occurs first

http://www.kz400.com

Engine Oil Change

The engine oil and oil filter are changed as follows:
eWarm up the engine thoroughly, and then stop the
engine.

@Set the motorcycle up on its center stand, place an
oil pan beneath the engine, and remove the engine
drain plug and oil filter.

eWipe off the drain plug removing any steel filings
which may be clinging to it (the drain plug is mag-
netic).

®After the oil has completely drained out, screw the
drain plug back in. Proper torque for the drain plug
is 2.7~3.3 kg-m (19.5~24 ft-lbs).

@Replace the oil filter with a new one if necessary, and
check that it is properly assembled (Pg. 27 ).

@|nstall the oi! filter tightening its bolt with 1.5 ~ 2.0
kg-m (11 ~ 14.5 ft-lbs) of torque.

ePour in 3 2 of SE or SD class SAE 10W40, 10W50,
or 20W50 motor oil,

NOTE: After the engine has been run and then stopped
for a few minutes, the oil level should come to between
the upper and lower marks.

Fuel Line Cleaning

Water or dirt anywhere in the fuel system can cause
starting difficulty, poor running, and lack of power.
Clean out the lines as follows:
eTurn the fuel tap to OFF. Unscrew the sediment

cup at the bottom of the tap, and clean out the water
and dirt from it, Clean any dirt out of the fuel tap
strainer.

elf there was water inside the sediment cup, there may
also be some in the fuel tank. Holding a container
under the fuel tap, turn the tap to RES to drain the
lank until gasoline only comes out, and then close the
lap.

@®Remove the plug from the side of each carburetor
float bowl to drain the bowls,

>.

4
he

APPENDIX 181

eReplace the plugs and the sediment cup, Make sure
that the O ring is in the tap and that the strainer ts
not damaged during installation,

General Lubrication

Lubrication of exposed parts subject to rust with
either SAE 30 motor oil or regular grease should be
carried out periodically and whenever the vehicle has
been operated under wet or rainy conditions, Before
lubricating each part, clean off any rusty spots with
rust remover. Badly rusted nuts, bolts, etc. should be
replaced with new ones,
®Lubricate the clutch cable, throttle cables, and front
brake cable (KZ400S) as shown in the figure.

k

®Lubricate the clutch lever pivot and brake lever pivot,
and the exposed portion of the clutch inner cable and
front brake inner cable.

eWipe off excess lubricant.

@Wipe clean the throttle grip inner surface and the
handlebar where the throttle grip fits,

@Apply grease to the handlebar where the throttle
grip turns,

®Apply a light coal of grease to the exposed porticn
of the throttle grip inner cables and their catches in
the throttle grip.

efit the throttle cables into the throttle grip.

http://www.kz400.com
182 APPENDIX

®Force grease into the fitting until it comes out at
both sides of the swing arm, and wipe off any excess,

eOil lightly the end of each drive chain adjuster, the
camshaft serration, and the end of the brake rod,
eWipe off excess oil,

®Lubricate the center stand pivol.

eWipe off any dirt or grime from around the left foot
peg, shift pedal, and side stand,

@Lubricate the exposed metal surfaces around the shift
pedal serration and the bolts and nuts for the left foot
peg and side stand.

®Wipe off excess lubricant,

®Oj! lightly the carburetor link mechanism and the choke
link mechanism,

Wipe off any dirt or grime from around the right foot
peg, brake pedal, and kickstarter pedal,

@lubricate the exposed metal surfaces around the bolts
and nuts for the right foot peg, brake pedal, and kick
starter pedal,

eWipe off excess lubricant.

@Oj| lightly around the camshaft serrations and where
the cam lever connects to the brake cable and the
connecting rod (KZ400S).

http://www.kz400.com APPENDIX 183

TORQUE TABLE

Tighten all bolts and nuts to the proper torque using an accurate torque wrench. A bolt or nut if
insufficiently tightened may become damaged or fall out, possibly resulting in damage to the motor-
cycle and injury to the rider. A bolt or nut which is over-tightened may become damaged, strip an
internal screw, or break and then fall out.

The following table lists the tightening torque for the major bolts and nuts:

Metric English see Pq.
Engine drain plug 2./~3.3 kg-m 19.5 ~ 24 ft-ibs 27,51,181
Oil filter bolt 1.5~ 2.0 kg-m 11~ 14.5 ft-lbs 27,51,181
Engine mounting bolts (3) 3.4~4.6 kg-m 25~ 33 ft-lbs 25
Engine mounting bracket bolts, front (3) 2.0~ 2.8 kg-m 14.5~ 20 ft-lbs 25
Engine mounting bracket bolts, rear (2) 1.6~ 2.2 kg-m 11.5~ 16 ft-lbs ~
Breather cover bolts 8? (4) 1.8~ 2.0 kg-m 13~14.5 ftlbs 26,32,35,38
Cylinder head cover nuts 8? (8) 2.5~ 3.0 kg-m 18~ 22 ft-lbs 32,35,38,70
Cylinder head bolts 8% (2) 2.5~ 3.0 kg-m 18~ 22 ft-lbs 38,70
Cylinder head bolts 6? (2) 1.1~ 1.3 kg-m 95~ 113 in-Ibs 38,70
Camshaft sprocket bolts 6” (2) 1.4~ 1.6 kg-m 10~ 11.5 ft-lbs 34,37,70
Rocker shaft nuts (4) 2.4~ 2.6 kg-m 18~ 22 ft-lbs 15
Dynamo rotor bolt 10 6.5~ 7.0 kg-m 47~51 ft-lbs 45,60
Starter clutch Allen bolts 8? (3) 3.3~ 3.7 kg-m 24~ 27 ft-lbs 46
Dynamo field coil Allen bolts 6” (3) 0.7~ 0.8 kg-m 61~ 69 in-lbs 43
Dynamo armature Allen bolts 6% (3) 0.7~0.8 kg-m 61~ 69 in-lbs 43,44
Engine sprocket nut 12~ 15 kg-m 87~ 108 ft-lbs 53,63
Crankcase bolts 8% (4) 2.5~ 3.0 kg-m 18~ 22 ft-Ibs 59
Crankcase bolts 6? (16) 0.8~ 1.0 kg-m 69 ~ 87 in-Ibs 59
Balancer holder bolts 6% (8) 2.3~ 2.7 kg-m 16.5~ 19.5 ft-lbs 66
Balancer weight bolts 6% (2) 1.1~ 1.3 kg-m 95~ 113 in-Ibs 66
Crankshaft bushing cap bolts 8° (4) 2.5~3.0 kg-m 18~ 22 ft-lbs 66
Connecting rod nuts 8° (4) 3.5~ 3.8 kg-m 25~ 27 ft-lbs 71
Timing advancer bolt 2.3~ 2.7 kg-m 16.5~ 19.5 ft-lbs 49 51,60
Neutral indicator switch 1.5~2.0 kg-m 11~ 14.5 ft-lbs 54
Oil pressure indicator switch 1.4~ 1.6 kg-m 10.0~ 11.5 ft-lbs 130
Front axle clamp nuts (2) 1.6~ 2.2 kg-m 11.5~ 16 ft-lbs 72,75
Front axle nut 7~9 kg-m 51~65 ft-lbs 72,75
Front fork top bolts (2) 2.5~ 3.0 kg-m 18~ 22 ft-lbs 93,95
Shock absorber upper clamp bolts (2) 1.6~ 2.2 kg-m 11.5~ 16 ft-lbs 93,95,96
Shock absorber lower clamp bolts (2) 2.0~ 3.0 kg-m 14.5~ 22 ft-lbs 16,93,95,97
Stem head clamp bolt 1.6~ 2.2 kg-m 11.5~ 16 ft-lbs 16,97
Stem head bolt 5.5 kg-m 40 ft-lbs 16
Handlebar clamp bolts (4) 1.6~ 2.2 kg-m 11.5~ 16 ft-lbs 88
Rear axle nut 10~ 14 kg-m 72~ 101 ft-lbs 21,78,87
Torque link nuts (4) (2 on KZ400D) 2.6~3.5 kg-m 19~ 25 ft-lbs 21,75,77,87,99
Rear sprocket nuts (4) 3.5~ 4.3 kg-m 25~ 31 ft-lbs 87
Rear shock absorber bolts (2) 2.6~ 3.5 kg-m 19~ 25 ft-lbs 99,100
Rear shock absorber cap nuts (2) 2.6~ 3.5 kg-m 19~ 25 ft-lbs 100
Swing arm pivot shaft nut 6~ 10 kg-m 43~ 72 ft-lbs 99
Steering stem lock nut 2.7~3.3 kg-m 19.5~ 24 ft-lbs 96
Disc brake parts - - 81
Spoke 0.2~0.4 ka-m 17~ 35 in-lbs 81,137
* Clutch spring bolts 0.9~ 1.1 kg-m 78~ 113 in-lbs 51,60

http:/Awww.kz400.com
184 APPENDIX

The table below, relating tightening torque to thread diameter and pitch, lists the basic torque for
the bolts and nuts used on Kawasaki Motorcycles. However, the actual torque that is necessary may
vary among bolts and nuts with the same thread diameter and pitch. The bolts and nuts listed on
Pg.183 vary to a greater or lesser extent from what is given in this table. Refer to this table for
only the bolts and nuts not included in the table on Pg.183. All of these values are for use with
dry solvent cleaned threads.

Coarse threads

dia (mm) pitch (mm) kg-m ft-lbs

5 0.80 0.35 ~ 0.50 25-35

6 1.00 0.6 ~ 0.9 4.5~6.5

8 1.25 1.6~ 2.2 11.5~ 16.0
10 1.50 3.1 ~ 4,2 22 ~ 30
12 1.75 5.4~ 7.5 39 ~ 54
14 2.00 83~ 11.5 60~ 83
16 2,00 13~ 18 94~ 130
18 2.50 18~ 25 130~ 181
20 2.50 26 ~ 35 188 ~ 253

Fine threads
dia (mm) pitch (mm) kg-m ft-lbs

5 0.50 0.35 ~ 0.50 2.5~3.5

6 0.75 0.6~ 0.8 4.5~5.5

8 1.00 1.4~19 10.0 ~ 13.5
10 1.25 2.6 ~ 3.5 19:0~ 25
12 1,50 45~6.2 33 ~ 45
14 1.50 7.4~ 10,2 54~ 74
16 1.50 11.5~ 16 83 ~ 116
18 1,50 17~ 23 123 ~ 166
20 1.50 23 ~ 33 166 ~ 239

http://www.kz400.com
APPENDIX 185

PARTS REQUIRING USE OF A NON-PERMANENT LOCKING AGENT

Camshaft Sprocket Bolts 2

See Pg.

34,37,70

Carburetor Mounting Screws

Clutch Release Mounting Screws

Dynamo Rotor Bolt |

Dynamo Field Coil Allen Bolts

o
Nh

; r Bee “fp
i)
af

|

45,60

43

Dynamo Armature Allen Bolts 43,44

Starter Motor Retaining Bolts 47,60

Starter Motor Clutch Allen Bolts

| Balancer Chain Guide Screws

Drive Chain Guide Screws

aa
o>

Primary Chain Guide Screws

Oil Pressure Relief Valve

External Shift Mechanism Stopper Screws

-_
Kh)
Oo)

Sump Plate Screws

Front: Fork Bottom: Allen Bolts

Oil Pressure Switch

_"
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= ‘ j r 3
| |

Pad B Mounting Screw

Front Brake Light Switch

x
i

RECOMMENDED LOCKING AGENTS

1. KAWASAKI LIQUID LOCK-K

2. NON-PERMANENT LOCTITE

http://www.kz400.com

186 APPENDIX
TROUBLESHOOTING GUIDE

Engine Doesn't Start; Starting Difficulty
Starter motor not rotating
Starter motor defective
Battery voltage low
Relay not contacting or operating
Starter button not contacting
Wiring open or shorted
lgnition switch defective
Engine stop switch defective
Fuse blown
Starter motor rotating but engine doesn't start
Starter motor cluich defective
Engine won't turn over
Valve seizure
Cylinder, piston seizure
Con-rod small end seizure
Con-rod big end seizure
Transmission gear or bearing seizure
Camshaft seizure
Kickstarter return spring broken
Kick ratchet gear not engaging
No fuel flow
No fuel in tank
Fuel tap turned off
Tank cap air vent obstructed
Fuel tap clogged
Fuel line clogged
Float valve clogged
Starter jet clogged
Engine flooded
Float level loo high
Float valve worn or stuck open
Starting technique faulty

(When flooded, kick with the throttle fully open to

allow more air to reach the engine.)
No spark; spark weak
Battery voltage low
Spark plug dirty, defective, or maladjusted

Spark plug cap or high tension wiring defective
Spark plug cap shorted or not in good contact

Contact breaker points dirly or damaged
Condenser defective
Ignition coil defective
Ignition or engine stop switch shorted
Wiring shorted or open

Compression low
Cylinder, piston worn

Piston rings bad (worn, weak, broken, or sticking)

Piston ring clearance excessive
Cylinder head gasket damaged

Cylinder head not sufficiently tightened down

Cylinder head warped

Spark plug loose

Valve sticking

Valve nol closing

Valve spring broken or weak

Valve nol sealing properly (valve bent, warped, or

worn)

Poor Running at Low Speed
Spark weak
Spark plug dirty, defective, or maladjusted

Spark plug cap or high tension wiring defective
Spark plug cap shorted or not in good contact
Contact breaker points dirty or damaged
Condenser defective

Ignition coil defective

Fuel/air mixture incorrect

Pilot screw(s) and/or throttle stop screw malad-
justed

Pilot jet, slow jet, or air passage clogged

Air cleaner clogged, poorly sealed, or missing

Starter plunger stuck open

Carburetor linkage not right

Float level too high or too low

Fuel tank air vent obstructed

Carburetor intake ducts loose

Compression low

Cylinder, piston worn

Piston rings bad (worn, weak, broken or sticking)

Piston ring clearance excessive

Cylinder head gasket damaged

Cylinder head not sufficiently tightened down

Cylinder head warped

Spark plug loose

Valve sticking

Valve not closing

Valve spring broken or weak

Valve not sealing properly (valve bent, warped, or
worn)

Other

Ignition timing maladjusted
Timing not advancing (spring broken or stretched)
Engine oil viscosity too high

Poor Running or No Power at High Speed
Firing incorrect

Spark plug dirty, defective, or maladjusted
Spark plug cap or high tension wiring defective
Spark plug cap shorted or not in good contact
Contact breaker points dirty or damaged
Condenser defective

Ignition coil defective

Ignition timing maladjusted

Contact breaker spring weak

Fuel/air mixture incorrect

Main jet clogged or wrong size

Jet needle or needle jet worn

Float level too high or too low

Needle jet bleed hole clogged

Air cleaner clogged, poorly sealed, or missing
Starter plunger stuck open

Water or foreign matter in fuel

Carburetor intake ducts loose

Fuel tank air vent obstructed

Compression low

Cylinder, piston worn

Piston rings bad (worn, weak, broken, or sticking)
Piston ring clearance excessive

Cylinder head gasket damaged

Cylinder head not sufficiently tightened down
Cylinder head warped

Spark plug loose

Valve sticking

Valve not closing

http://www.kz400,com

Valve spring broken or weak

Valve not seating properly (valve bent, warped, or

worn)

Knocking

Ignition timing maladjusted

Carbon built up in combustion chamber

Fuel poor quality or incorrect
Miscellaneous

Throttle valve won't fully open

lgnition Liming maladjusted

Timing not advancing

Balancer mechanism malfunctioning

Brakes dragging

Clutch slipping

Overheating

Engine oil level too high

Engine oil viscosity too high

Overheating
Firing incorrect
Spark plug dirty, damaged, or maladjusted
Ignition timing maladjusted
Fuel/air mixture incorrect
Main jet clogged
Float level too low
Carburetor intake ducts loose
Air cleaner clogged
Compression high
Carbon built up in combustion chamber
Engine load faulty
Clutch slipping
Engine oil level too high
Brakes dragging
Lubrication inadequate
Engine oil level too low

Clutch Operation Faulty
Clutch slipping
No clutch lever play
Friction plates worn or warped
Steel plates worn or warped
Clutch springs weak
Clutch cable maladjusted
Clutch inner cable catching
Clutch release mechanism defective
Clutch hub or housing unevenly worn
Clutch not disengaging properly
Clutch lever play excessive
Clutch plates warped or too rough
Clutch spring tension uneven
Engine oil deteriorated
Engine oil of too high a viscosity
Clutch housing frozen on drive shaft
Clutch release mechanism defective

Gear Shifting Faulty

Doesn't go into gear; shift pedal doesn’t return

Clutch not disengaging

Shift fork(s) bent or seized

Shift return spring weak or broken
External shift mechanism pawl broken
Shift return spring pin loose

External shift mechanism arm spring broken

Jumps out of gear

Shift fork(s) worn

Gear groove(s) worn

Gear dogs, dog holes, and/or dog recesses worn
Shift drum groove(s) worn

Shift drum positioning pin spring weak or broken
Shift fork pin(s) worn

External shift mechanism arm spring or pawl worn
Drive shaft, output shaft, and/or gear splines worn

Overshifts

Shift return spring pin loose

Abnormal Engine Noise
Knocking

Ignition timing maladjusted

Carbon built up in combustion chamber
Fuel poor quality or incorrect
Overheating

Piston slap

Cylinder/piston clearance excessive
Cylinder, piston worn

Con-rod bent

Piston pin, piston holes worn

Valve noise

Valve clearance incorrect
Valve spring broken or weak
Camshaft bearings worn

Other noise

Con-rod small end clearance excessive
Con-rod big end clearance excessive

Piston ring(s) worn, broken, or stuck

Piston seizure damage

Cylinder head gasket leaking

Exhaust pipe leaking at cylinder head connection
Crankshaft runout excessive

Engine mounts loose

Crankshaft bearings worn

Primary chain, chain guides worn

Starter motor chain, chain guides worn
Balancer chain, chain guides worn

Camshaft chain tensioner defective
Camshaft chain, sprocket, guides worn
Camshaft chain requires adjustment
Balancer mechanism springs weak or broken

Abnormal Drive Train Noise
Clutch noise

Clutch housing/friction plate clearance excessive

Transmission noise

Bearings worn

Transmission gears worn or chipped

Metal chips jammed in gear teeth

Engine oil insufficient or too thin

Kick ratchet gear not properly disengaging
from kick gear

Drive chain noise

Chain worn

Rear and/or engine sprocket(s) worn
Chain lubrication insufficient

Rear wheel misaligned

APPENDIX 187

http://Avwww.kz400.com

188 APPENDIX

Abnormal Frame Noise

Front fork shock absorber noise
Oil insufficient or too thin
Spring weak or broken

Rear shock absorber noise
Shock absorber defective

Dise brake noise
Pad B loose
Pad surface glazed
Disc warped
Caliper seal defective
Cylinder damaged

Drum brake noise
Brake linings overworn or worn unevenly
Drum worn unevenly or scored
Brake spring weak or broken
Foreign matter in hub
Brake not properly adjusted

Other noise

Brackets, nuts, bolts, etc. not properly mounted

or tightened

Oil Pressure Indicator Light Goes On
Engine oil pump defective
Engine oil screen clogged
Engine oil level too low
Camshaft journals worn
Crankshaft bearings worn
Oil pressure indicator light switch defective
Wiring defective

Exhaust Smoke
White smoke
Piston oil ring worn
Cylinder worn
Valve guide worn
Engine oil level too high
Black smoke
Air cleaner clogged
Main jet too large or fallen off
Starter plunger stuck open
Float level too high
Brown smoke
Main jet too small
Float level too low
Carburetor intake ducts loose

Handling and/or Stability Unsatisfactory

Handlebar hard to turn
Steering stem lock nul too tight
Bearing balls damaged
Race(s) dented or worn
Steering stem lubrication inadequate
Steering stem bent
Tire air pressure too low

Handlebar shakes or excessively vibrates
Tire(s) worn
Swing arm bushing damaged
Rim(s) warped, or not balanced
Front, rear axle runoul excessive
Spokes loose
Wheel bearing(s) worn
Handlebar clamps loose

Handlebar pulls to one side

Frame bent

Wheel misalignment

Swing arm bent or twisted

Swing arm pivot shaft runout excessive

Steering slem bent

Front fork shock absorber(s) bent

Right/left front fork shock absorber oil level

uneven

Right/left rear shock absorbers unbalanced
Shock absorption unsatisfactory

Too hard:

Front fork oil excessive

Front fork oil viscosity too high

Tire air pressure too high

Shock absorber maladjusted

Too soft:

Front fork oil insufficient and/or leaking

Front fork oil viscosity Loo low

Front fork, rear shock absorber spring(s) weak

Rear shock absorber oil leaking

Brakes Don't Hold

Disc Brake
Air in the brake line
Pad or disc worn
Brake fluid leak
Brake fluid deteriorated
Primary or secondary cup defective
Master cylinder scratched inside
Drum brake
Brake maladjusted
Brake lining or drum worn
Overheated
Water on brake drum
Brake cam, camshaft worn
Oil on brake linings

Battery Discharged

Battery faulty (e.g. plates sulphated, shorted
through sedimentation, electrolyte level too low)

Battery leads making poor contact

Rectifier defective

Iznition switch defective

Regulator defective

Armature coil open or short

Wiring faulty

Battery Overcharged
Regulator defective or wiring open
Dynamo defective
Battery defective

NOTE: This is not an exhaustive list, giving every
possible cause for each problem listed. It is meant
simply as a rough guide to assist the troubleshooting
for some of the more common difficulties, Electrical
troubleshooting is not covered here due lo its com-
plexity. For electrical problems, refer to the appropriate
heading in the Maintenance Section,

KZ400D Wiring Diagram

(US Model)

APPENDIX 189

190 APPENDIX http://www.kz400.com

1

KZ400D Wiring Diagram
(European model)

http://www.kz400.com APPENDIX 191

ng Diagram

KZ400S Wir

SUPPLEMENT 201

http://www.kz400.com

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KZ400-D4 Wiring Diagram

http://www.kz400.com
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KZ400-S3 Wiring Diagram

Front Aigns Turn Sigeal ~—— :
Light 12 230 (a=5 eed ashe

Fear Brake © Twin Signal Light Pielay
Light Seiten | 12V 23Wa2+3,4W

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Speedometer Light : a i :
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